delivered the opinion of the Court.*

The Government seeks to appeal to this Court a decision by a District Court in Massachusetts holding that appellee Sisson could not be criminally convicted for refusing induction into the Armed Forces. TheJDistrict Court’s opinion was bottomed on what that..court-under*270stood to be Sisson’s rights of conscience as a nonreligious objector to the Vietnam war, but not wars in general, under the Free Exercise and Establishment Clauses of the First Amendment and the Due Process Clause of the Fifth Amendment to the Constitution of the United States. The District Court’s primary conclusion, reached after a full trial, was that the Constitution prohibited “the application of the 1967 draft act to Sisson to require him to render combat service in Vietnam” because as a “sincerely conscientious man,” Sisson’s interest in not killing in the Vietnam conflict outweighed “the country’s present need for him to be so employed,” 297 F. Supp. 902, 910 (1969).

The District Court characterized its own decision as an arrest of judgment, and the Government seeks review here pursuant to the “arresting judgment” provision of the Criminal Appeals Act, 18 U. S. C. § 3731, an Act that narrowly limits the Government’s right to appeal in criminal cases to certain types of decisions. On October 13, 1969, this Court entered an order postponing further consideration of the question of jurisdiction to the hearing of the case on the merits, 396 U. S. 812 (1969). For reasons that we elaborate in what follows, we conclude that the decision below, depending as it does on facts developed at Sisson’s trial, is not an arrest of judgment but instead is a directed acquittal. As such, it is not a decision that the Government can appeal. Consequently, this appeal must be dismissed for lack of jurisdiction without our considering the merits of this case. We, of course, intimate no view concerning the correctness of the legal theory by which the District Court evaluated the facts developed at the trial.1

*271As a predicate for our conclusion that we have no jurisdiction to entertain the Government’s appeal, a full statement of the proceedings below is desirable.

I

A single-count indictment charged that Sisson "did unlawfully, knowingly and wilfully fail and neglect and refuse to perform a duty” imposed by the Military Selective Service Act of 1967 and its regulations, in violation of § 12 of the Act, 81 Stat. 105, 50 U. S. C. App. § 462 (a) (1964 ed., Supp. IV), because he failed to obey an order by his local draft board to submit to induction.

Prior to trial, Sisson’s attorney moved to dismiss the indictment on three grounds. It was claimed that Sisson’s refusal to submit to induction was justified first, because “the government’s military involvement in Vietnam violates international law”; and, second, because Sisson “reasonably believed the government’s military involvement in Vietnam to be illegal.” As a third ground, Sisson claimed that the Selective Service Act and its regulations were unconstitutional (a) because the procedures followed by local boards lacked due process; and (b) because compulsory conscription during peacetime was unnecessary and stifled fundamental personal liberties. In support of the motion to dismiss, appellee stated:

“At the time I refused to submit to induction into the armed forces I believed, as I believe today, that the United States military involvement in Vietnam is illegal under international law as well as under the Constitution and treaties of the United States. I believed then, and still believe, that my participation in that war would violate the spirit and the letter of the Nuremberg Charter. On the basis of my knowledge of that war, I could not participate in it without doing violence to the dictates of my conscience.”

*272At the hearing on appellee’s motion to dismiss, the District Judge said that he had “an open mind” concerning appellee’s first and third grounds. However, the court said there was “nothing to” the second ground, noting that what “the defendant reasonably believes . . . cannot be raised in the way that you propose . . . because that does not appear on the face of the indictment.” (App. 49.) The District Court later amplified this conclusion by saying:

“Point 2 is plainly premature because nobody can test the issue as to whether defendant reasonably believes the government’s military involvement in Vietnam is illegal without knowing what he reasonably believed, and what he believed is a question of evidence and not a question which appears on the face of the indictment.” (App. 52.) (Emphasis supplied.)

Defense counsel did not dispute the District Court’s analysis, and noted that he had raised the issue in his motion to dismiss only “in the interest of economy,” because “[i]t was not clear at the time I filed the motion that the government would challenge this fact.” (App. 52.) The court expressed doubts concerning the Government’s willingness to concede this fact, and, when asked by the court, the government counsel specifically stated his opposition to the motion to dismiss. The court thereupon found the “second ground” of the motion to dismiss without merit.

A short time after this hearing, the District Court issued two written opinions, 294 F. Supp. 511 and 515 (1968), that denied the other grounds of the motion to dismiss. After determining that appellee had the requisite standing to raise the issues involved, the court held that the political question doctrine foreclosed consideration of whether Congress could constitutionally draft for *273an undeclared war, or could order Sisson to fight in the allegedly “genocidal war.”

An order accompanying the second pretrial opinion also dealt with various offers of proof that defense counsel had made in an informal letter to the court, not part of the record. From the order it appears that appellee’s counsel stated he would “offer evidence to show that [Sisson] properly refused to be inducted on the basis of his right of conscience, both statutory and constitutional.” Not understanding the scope of this rather ambiguous offer of proof, the District Court in its order ruled that if Sisson wished to make a conscientious objector claim based on religious objections not to wars in general but to the Vietnam war in particular, Sisson should make his offer of proof initially to the judge

“to elicit a ruling whether the First Amendment precludes the Congress from requiring one who has religious conscientious objections to the Vietnam war to respond to the induction order he received. If the Court rules favorably to defendant on the Constitutional issue of law, then both defense and prosecution are entitled to submit to the trier of fact evidence relevant to the question whether defendant indeed is a religious conscientious objector to the Vietnam war.” 294 F. Supp., at 519.

At the trial, however, it appears that defense counsel did not try to prove that Sisson should have received a conscientious objector exemption, nor did he request a ruling on the First Amendment issues referred to by the trial court. Instead it seems that the defense strategy was to prove that Sisson believed the Vietnam war to be illegal under domestic and international law, and that this belief was reasonable. If unable to get a direct adjudication of the legality of the war, the defense at least *274hoped to convince the jury that Sisson lacked the requisite intent to “wilfully” refuse induction.2

There was evidence submitted at the trial that did bear on the conscientious objector issue, however. When asked why he had refused induction, Sisson emphasized that he thought the war illegal. He also said that he felt the Vietnam war was “immoral,” “illegal,” and “unjust,” and went against “my principles and my best sense of what was right.” The court asked Sisson what the basis for his conclusions was, particularly what Sisson meant when he said the war was immoral. Sisson said that the war violated his feelings about (1) respect for human life, (2) value of man’s freedom, and (3) the scale of destruction and killing consonant with the stated purposes of American intervention. Sisson also stated, in response to the trial judge’s question, that his “moral values come from the same sources [the trial court had] mentioned, religious writings, philosophical beliefs.”

The prosecution did not allow Sisson’s testimony to stand without cross-examination. In apparent reliance *275on the court’s pretrial ruling that Sisson’s beliefs concerning the war were irrelevant to the question of whether his refusal to submit to induction was wilful3 the government counsel concentrated on showing that Sisson had refused induction deliberately, of his own free will, and knowing the consequences. The prosecution also brought out that Sisson had failed to appeal his I-A classification when it had been issued, and that he had accepted, as an undergraduate, a II-S student classification.

In the final arguments to the jury, just as in the opening statements, neither counsel mentioned a religious or nonreligious conscientious objector issue. The defense argued that the key to the case was whether Sisson had “wilfully” refused to submit to induction, and tried to suggest his beliefs about the war were relevant to this. The government lawyer simply pointed out the operative facts of Sisson’s refusal. He also attacked Sisson’s sincerity by pointing out the inconsistency between Sissons’ broad statements that he opposed deferments because they discriminated against the poor, *276see n. 2, supra, and his willingness to accept a II-S deferment while he was at Harvard College. (See App. 187-188.)

The instructions to the jury made no reference to a conscientious objector claim, and the jury was not asked to find whether Sisson was “sincere” in his moral beliefs concerning the war. Instead the trial court told the jury that the crux of the case was whether Sisson’s refusal to submit to induction was “unlawfully, knowingly and wilfully” done,4 The jury, after deliberating about 20 minutes, brought in a verdict of guilty.

After the trial, the defendant made a timely motion under Fed. Rule Crim. Proc. 34 to arrest the judgment on the ground that the District Court lacked jurisdiction.5 Pointing to the fact that the District Court had ruled before the trial that the political question doctrine prevented its consideration of defenses requiring an adjudication of the legality of the Vietnam war, the defense *277argued that the court therefore lacked jurisdiction under Article III and the Due Process Clause to try the defendant for an offense to which the illegality of the war might provide a defense.

The District Court, in granting what it termed a motion in arrest of judgment, did not rule on the jurisdictional argument raised in the defense motion. Instead, the court ruled on what it termed defendant’s “older contention” 6 that the indictment did not charge an offense based on defendant’s “never-abandoned” Establishment, Free Exercise, and Due Process Clause arguments relating to conscientious objections to the Vietnam war.

The court first stated the facts of the case, in effect making findings essential to its decision. The opinion *278describes how Sisson’s demeanor on the stand convinced the court of his sincerity. The court stated that “Sisson’s table of ultimate values is moral and ethical. . . [and] reflects quite as real, pervasive, durable, and commendable a marshalling of priorities as a formal religion.” The critical finding for what followed was that:

“What another derives from the discipline of a church, Sisson derives from the discipline of conscience.

“. . . Sisson bore the burden of proving by objective evidence that he was sincere. He was as genuinely and profoundly governed by his conscience as would have been a martyr obedient to an orthodox religion.” 297 F. Supp., at 905.

Building on these findings, the court first held that the Free Exercise and Due Process Clauses “prohibit the application of the 1967 draft act to Sisson to require him to render combat service in Vietnam” because as a “sincerely conscientious man,” Sisson’s interest in not killing in the Vietnam conflict outweighed “the country’s present need for him to be so employed.” The District Court also ruled that § 6 (j) of the Selective Service Act, 50 U. S. C. App. §456 (j) (1964 ed., Supp. IV), offends the Establishment Clause because it “unconstitutionally discriminated against atheists, agnostics, and men, like Sisson, who, whether they be religious or not, are motivated in their objection to the draft by profound moral beliefs which constitute the central convictions of their beings.” 297 F. Supp., at 911.

II

The Government bases its claim that this Court has jurisdiction to review the District Court’s decision exclusively on the “arresting judgment” provision of the *279Criminal Appeals Act, 18 U. S. C. § 37317 The relevant statutory language provides:

“An appeal may be taken by and on behalf of the United States from the district courts direct to the Supreme Court of the United States in all criminal cases in the following instances:

“From a decision arresting a judgment of conviction for insufficiency of the indictment or information, where such decision is based upon the invalidity or construction of the statute upon which the indictment or information is founded/’

Thus, three requirements must be met for this Court to have jurisdiction under this provision. First, the decision of the District Court must be one “arresting a judgment of conviction.” Second, the arrest of judg*280ment must be for the “insufficiency of the indictment or information.” And third, the decision must be “based upon the invalidity or construction of the statute upon which the indictment or information is founded.”8

Because the District Court’s decision rests on facts not alleged in the indictment but instead inferred by the court from the evidence adduced at trial, we conclude that neither the first nor second requirement is met.9

A

We begin with the first requirement: was the decision below one “arresting a judgment of conviction”? In using that phrase in the Criminal Appeals Act, Congress did not, of course, invent a new procedural classification. Instead, Congress acted against a common-law background that gave the statutory phrase a well-defined and limited meaning. An arrest of judgment was the technical term describing the act of a trial, judge refusing to enter judgment on the verdict because of an error appearing on the face of the record that rendered the judgment *281invalid. 3 W. Blackstone, Commentaries *393; 3 H. Stephen, New Commentaries on the Laws of England 628 (1st Am. ed. 1845); 2 J. Bishop, New Criminal Procedure § 1285 (2d ed. 1913).

For the purpose of this case the critical requirement is that a judgment can be arrested only on the basis of error appearing on the “face of the record,” and not on the basis of proof offered at trial.10 This requirement can be found in early English common-law cases. In Sutton v. Bishop, 4 Burr. 2283, 2287, 98 Eng. Rep. 191, 193 (K. B. 1769), it was stated: “[T]he Court ought not to arrest judgments upon matters not appearing upon the face of the record; but are to judge upon the record itself.” Once transported to the United States,11 this essential limitation of arrests of judgment was explicitly acknowledged by this Court. In United States v. Klintock, 5 Wheat. 144, 149 (1820), the Court stated that “judgment can be arrested only for errors apparent on the record.” And later in Bond v. Dustin, 112 U. S. 604 (1884), the Court said, “[A] motion in arrest of judgment can only be maintained for a defect apparent upon the face of the record, and the evidence is no part of the record for this purpose,” id., at 608. See Carter v. Bennett, 15 How. 354, 356-357 (1854); United States v. Norris, 281 U. S. 619 (1930).

This venerable requirement of the common law has been preserved under the Federal Rules of Criminal Procedure, for the courts have uniformly held that in grant*282ing a motion in arrest of judgment under Rule 34,12 a district court must not look beyond the face of the record. E. g., United States v. Zisblatt, 172 F. 2d 740 (C. A. 2d Cir.), appeal dismissed on Government’s motion, 336 U. S. 934 (1949); United States v. Lias, 173 F. 2d 685 (C. A. 4th Cir. 1949); United States v. Bradford, 194 F. 2d 197 (C. A. 2d Cir. 1952). See 2 C. Wright, Federal Practice and Procedure § 571 (1969); 5 L. Orfield, Criminal Procedure Under the Federal Rules § 34:7 (1967). Therefore, whether we interpret the statutory phrase “decision arresting a judgment” as speaking “to the law, as it then was [in 1907] ... as it had come down from the past,”13 or do no more than interpret it as simply imposing the standards of Fed. Rule Crim. Proc. 34,14 a decision based on evidence adduced at trial cannot be one arresting judgment.15

*283The court below clearly went beyond the “face of the record” in reaching its decision. As noted earlier, the opinion explicitly relies upon the evidence adduced at the trial, including demeanor evidence, for its findings that Sisson was “sincere” and that he was “as genuinely and profoundly governed by his conscience” as a religious conscientious objector.

To avoid the inescapable conclusion that the District Court's opinion was not an arrest of judgment, the Government makes two arguments. First, the Government suggests that these factual findings of the District Court, based on the evidence presented at trial, were not essential to its constitutional rulings, but instead only part of “the circumstantial framework” of the opinion below. (Jurisdictional Statement 9; see Brief 8.) This *284cannot withstand analysis, however, for the factual findings were absolutely essential, under the District Court’s own legal theory, to its disposition of the case. Without a finding that Sisson was sincerely and fundamentally opposed to participation in the Vietnam conflict, the District Court could not have ruled that under the Due Process and Free Exercise Clauses Sisson’s interest in not serving in Vietnam outweighed the Government’s need to draft him for such service.16

Second, the Government argues that even though the District Court made findings on evidence adduced at trial, the facts relied on were “undisputed.” Adopting the language used by the court below, the Government claims that “in substance the case arises upon an agreed statement of facts.” 297 F. Supp., at 904. The Government then goes on to argue that decisions of this Court have “recognized that a stipulation of facts by the parties in a criminal case” can be relied on by the District Court without affecting the jurisdiction for an appeal, citing United States v. Halseth, 342 U. S. 277 (1952), and United States v. Fruehauf, 365 U. S. *285146 (1961). The Government then concludes that it would be exalting form over substance to hold there was no appeal in a case where the Government has not contested the facts, and yet allow an appeal to lie from a motion to dismiss resting upon a stipulation of the parties.

Preliminarily, it should be noted that this Court has never held that an appeal lies from a decision which depends, not upon the sufficiency of the indictment alone, but also on a stipulation of the parties. In Halseth the parties did enter into a stipulation for purposes of a motion to dismiss. But the facts in the stipulation were irrelevant to the legal issue of whether the federal anti-lottery statute reached a game not yet in existence. Therefore, neither the District Court in dismissing the indictment, nor this Court in affirming its decision, had to rely on the stipulation. And, for purposes of deciding whether jurisdiction for an appeal under § 3731 existed, the Court obviously did not have to decide — and it did not discuss — whether reliance on a stipulation would make any difference. Insofar as United States v. Fruehauf, supra, the other case cited by the Government, is relevant at all it seems to point away from the Government’s contention. In Fruehauj this Court refused to consider the merits of an appeal under § 3731 from a District Court decision dismissing an indictment on the basis of a “ ‘judicial admission’ culled from a pretrial memorandum” of the Government by the District Judge. Rather than penalizing the Government by dismissing the appeal, however, the Court simply exercised its discretion under 28 U. S. C. § 2106 by setting aside the ruling below, and remanding the case for a new trial on the existing indictment.

Not only do the cases cited by the Government fail to establish its contention, but other authority points strongly in the opposite direction. In United States v. Norris, 281 U. S. 619 (1930), this Court said that a “stip*286ulation was ineffective to import an issue as to the sufficiency of the indictment, or an issue of fact upon the question of guilt or innocence,” because of “the rule that nothing can be added to an indictment without the concurrence of the grand jury,” id., at 622. While it is true that Norris is complicated by the fact that the defendant had entered a guilty plea, the Court said that even “[i]f [the stipulation had been] filed before plea and [had been] given effect, such a stipulation would oust the jurisdiction of the court,” id., at 622-623. Norris, together with the policy, often expressed by this Court, that the Criminal Appeals Act should be strictly construed against the Government’s right to appeal, see, e. g., United States v. Borden Co., 308 U. S. 188, 192 (1939), makes it at least very doubtful whether the parties should, on the basis of a stipulation, be able to secure review under the motion-in-arrest provisions of § 3731.

We do not decide that issue, however, for there was nothing even approaching a stipulation here. Before the court’s final ruling below, the parties did not in any way, formally or informally, agree on the factual findings made in its opinion. It is relevant to recall that before the trial the government attorney specifically refused to stipulate whether Sisson sincerely believed the war to be illegal, and, if so, whether such a belief was reasonable. Moreover, given that the government attorney cross-examined Sisson, and later pointed out the inconsistency between Sisson’s acceptance of a II-S student deferment and his claim that he disapproved of deferments as unfair, it hardly seems the Government accepted Sisson’s sincerity insofar as it was an issue in the case. Therefore, far from being like a case with a formal stipulation between the parties, the most that can be said is that after the District Court’s decision the Government chose to accept the opinion’s findings of fact. Even assuming reliance on a formal stipulation were per*287missible, it would still be intolerable to allow direct review whenever the District Court labels its decision a motion in arrest, and the Government merely accepts the lower court’s factual findings made after a trial — for this would mean the parties and the lower court simply could foist jurisdiction upon this Court.

B

The second statutory requirement, that the decision arresting judgment be “for insufficiency of the indict-meht,” is also not met in this case. Senator Nelson, one of the sponsors of the Criminal Appeals Act, made it plain during the debates that this second element was an important limitation. He said:

“The arrest of judgment ... on which an appeal lies, is not a general motion covering all the grounds on which a judgment may be arrested. It is simply for arrest of judgment because of the insufficiency of the indictment — that is, the failure of the indictment to charge a criminal offense.” 41 Cong. Rec. 2756. (Emphasis supplied.)

See also 40 Cong. Rec. 9033. Although the District Court’s opinion recites as a conclusion that the indictment in this case did “not charge an offense” for purposes of Rule 34, surely the indictment alleged the necessary elements of an offense.17 The deci*288sion below rests on affirmative defenses which the court thought Sisson could claim because of his beliefs. It has never been thought that an indictment, in order to be sufficient, need anticipate affirmative defenses, United States v. Fargas, 267 F. Supp. 452, 455 (D. C. S. D. N. Y. 1967) (“Any questions as to the validity of the local board’s refusal to grant conscientious objector exemption are matters of defense . . . [that] [t]here is no necessity for the indictment to negate . . Moreover, even assuming, arguendo, the correctness of the District Court’s constitutional theory that sincere nonreligious objectors to particular wars have a constitutional privilege that bars conviction, the facts essential to Sisson’s claim of this privilege do not appear from any recitals in the indictment. As the District Court itself said before trial, “[W]hat [Sisson] believed is a question of evidence and not a question which appears on the face of the indictment.” (App. 52.) In short, this indictment cannot be taken as insufficient for, on the one hand, it recites the necessary elements of an offense, and on the other hand, it does not allege facts that themselves demonstrate the availability of a constitutional privilege.

C

The same reason underlying our conclusion that this was not a decision arresting judgment — i.e., that the disposition is bottomed on factual conclusions not found in the indictment but instead made on the basis of evidence adduced at the trial — convinces us that the decision was in fact an acquittal rendered by the trial court after the jury’s verdict of guilty.

*289For purposes of analysis it is helpful to compare this case to one in which a jury was instructed as follows:

“If you find defendant Sisson to be sincere, and if you find that he was as genuinely and profoundly governed by conscience as a martyr obedient to an orthodox religion, you must acquit him because the government’s interest in having him serve in Vietnam is outweighed by his interest in obeying the dictates of his conscience. On the other hand, if you do not so find, you must convict if you find that petitioner did wilfully refuse induction.”

If a jury had been so instructed, there can be no doubt that its verdict of acquittal could not be appealed under § 3731 no matter how erroneous the constitutional theory underlying the instructions. As Senator Knox said of the bill that was to become the Criminal Appeals Act:

“Mark this: It is not proposed to give the Government any appeal under any circumstances when the defendant is acquitted for any error whatever committed by the court.

“The Government takes the risks of all the mistakes of its prosecuting officers and of the trial judge in the trial, and it is only proposed to give it an appeal upon questions of law raised by the defendant to defeat the trial and if it defeats the trial.

“The defendant gets the benefit of all errors in the trial which are in his favor, and can challenge all errors in the trial which are against him.” 41 Cong. Rec. 2752.

Quite apart from the statute, it is, of course, well settled that an acquittal can “not be reviewed, on error or otherwise, without putting [the defendant] twice in jeopardy, and thereby violating the Constitution. ... [I]n this country a verdict of acquittal, although not followed by *290any judgment, is a bar to a subsequent prosecution for the same offence,” United States v. Ball, 163 U. S. 662, 671 (1896).18

There are three differences between the hypothetical case just suggested and the case at hand. First, in this case it was the judge — not the jury — who made the factual determinations. This difference alone does not support a legal distinction, however, for judges, like juries, can acquit defendants, see Fed. Rule Crim. Proc. 29. Second, the judge in this case made his decision after the jury had brought in a verdict of guilty. Rules 29 (b) and (c) of the Federal Rules of Criminal Procedure, however, expressly allow a federal judge to acquit a criminal defendant after the jury “returns a verdict of guilty.” And third, in this case the District Judge labeled his post-verdict opinion an arrest of judgment, not an acquittal. This characterization alone, however, neither confers jurisdiction on this Court, see n. 7, supra, nor makes the opinion any less dependent upon evidence adduced at the trial. In short, we see no distinction between what the court below did, and a post-verdict directed acquittal.19

*291rH i — I h-i

The dissenting opinions of both The Chief Justice and Mr. Justice White suggest that we are too niggardly-in our interpretation of the Criminal Appeals Act, and each contends that the Act should be more broadly construed to give effect to an underlying policy that is said to favor review. This Court has frequently stated that the “exceptional right of appeal given to the Government by the Criminal Appeals Act is strictly limited to the instances specified,” United States v. Borden Co., 308 U. S. 188, 192 (1939), and that such appeals “are something unusual, exceptional, not favored,” Carroll v. United States, 354 U. S. 394, 400 (1957); see United States v. Keitel, 211 U. S. 370, 399 (1908); United States v. Dickinson, 213 U. S. 92, 103 (1909); cf. Will v. United States, 389 U. S. 90, 96 (1967). The approach suggested by our Brothers seems inconsistent with these notions. Moreover, the background and legislative history of the Criminal Appeals Act demonstrate the compromise origins of the Act that justify the principle of strict construction this Court has always said should be placed on its provisions. Because the Criminal Appeals Act, *292now 18 U. S. C. §3731 (1964 ed., Supp. IV),20 has descended unchanged in substance from the original Criminal Appeals Act, which was enacted on March 2, 1907, 34 Stat. 1246,21 the crucial focus for this inquiry must be the legislative history of the 1907 Act.22

*293A

Beginning in 1892 — 15 years before the enactment of the Criminal Appeals Act — the Attorneys General of the United States regularly recommended passage of legislation allowing the Government to appeal in criminal cases.23 Their primary purpose was perhaps best expressed by Attorney General Miller in his 1892 report: “As the law now stands ... it is in the power of a single district judge, by quashing an indictment, to defeat any criminal prosecution instituted by the Government.”24 There was no progress, however, until President Theodore Roosevelt, outraged by a decision of *294Judge Humphrey preventing the prosecution of the Beef Trust,25 made this proposed reform into a “major political issue,”26 and demanded the enactment of legislation in his 1906 annual message to Congress.27

The House, as one commentator has written, “was obedient to the presidential command.”28 It passed, without debate,29 a very broad bill giving the Government the same right to appeal legal issues decided adversely to it as had earlier been accorded a criminal defendant.30 The Senate would not accept any such sweeping change of the traditional common-law rule giving the Government no appeal at all. The substitute bill that the Senate Judiciary Committee reported out31 narrowed the House bill substantially, and limited the Government's right to appeal to writs of error from decisions (1) quashing an indictment or sustaining a demurrer to an indictment; (2) arresting judgment of conviction because of the insufficiency of the indictment; and (3) sustaining special pleas in bar when the defendant had not been put in jeopardy. Even as narrowed, *295the bill met opposition on the floor,32 and the session closed without Senate action.33

The next session, after the bill was again reported out of the Senate Judiciary Committee,34 it was debated for three days on the floor and again met strong opposition.35 Reflecting the deep concern that the legislation not jeopardize interests of defendants whose cases were appealed by the Government, amendments were adopted requiring the Government to appeal within 30 days and to prosecute its cases with diligence;36 and allowing defendants whose eases were appealed to be released on their own recognizance in the discretion of the presiding judge.37 Various Senators were particularly concerned lest there be any possibility that a defendant who had already been through one trial be subjected to another trial after a successful appeal by the Government.38 In response to this concern, an amendment was then adopted requiring that a verdict in favor of the defendant not be set aside on appeal39 no matter how erroneous the legal theory upon which it might be based.40 For these purposes, it was made plain that it made no difference whether the verdict be the result of the jury’s decision or that of the judge.41 Moreover, as we explore in more detail later, *296the debates suggest that apart from decisions arresting judgment, there were to be no appeals taken in any case in which jeopardy had attached by the impaneling of the jury.42 Finally, to limit further the scope of the Act to cases of public importance, the Government’s right to appeal (under all but the special plea in bar provision) was confined to cases in which the ground of the District Court’s decision was the “invalidity or construction of the statute upon which the indictment is founded.”43

With all these amendments the Senate passed the bill without division on February 13, 1907,44 but the House, after referring the Senate’s version to its Judiciary Committee,45 disagreed with the Senate bill and proposed a conference.46 The conference committee, apart from divesting the courts of appeals of jurisdiction to hear any government appeals, adopted the Senate version of the bill with merely formal changes.47 Both the Senate and the House approved the bill reported out by the committee 48 and with the President’s signature the Criminal Appeals Act became law.

B

With this perspective, we now examine the arguments made in opposition to our conclusion. It is argued in *297dissent that § 3731 “contemplates that an arrest of judgment is appropriate in other than a closed category of cases defined by legal history,” and concludes that “evidence adduced at trial can be considered by a district court as the basis for a motion in arrest of judgment when that evidence is used solely for the purpose of testing the constitutionality of the charging statute as applied,” post, at 314 (dissenting opinion of The Chief Justice).

The dissenters propose in effect to create a new procedure — label it a decision arresting judgment — in order to conclude that this Court has jurisdiction to hear this appeal by the Government. The statutory phrase “decision arresting a judgment” is not an empty vessel into which this Court is free to pour a vintage that we think better suits present-day tastes. As we have shown, Congress defined our jurisdiction in the Criminal Appeals Act in terms of procedures existing in 1907. As a matter of interpretation, this Court has no right to give the statutory language a meaning inconsistent with its common-law antecedents, and alien to the limitations that today govern motions in arrest of judgment under Rule 34.49

Radical reinterpretations of the statutory phrase “decision arresting a judgment” are said to be necessary in order to effectuate a broad policy, found to be underlying the Criminal Appeals Act, that this Court review important legal issues. The axiom that courts should endeavor to give statutory language that meaning that nurtures the policies underlying legislation is one that *298guides us when circumstances not plainly covered by the terms of a statute are subsumed by the underlying policies to which Congress was committed. Care must be taken, however, to respect the limits up to which Congress was prepared to enact a particular policy, especially when the boundaries of a statute are drawn as a compromise resulting from the countervailing pressures of other policies. Our disagreeing Brothers, in seeking to energize the congressional commitment to review, ignore the subtlety of the compromise that limited our jurisdiction, thereby garnering the votes necessary to enact the Criminal Appeals Act.50

In this regard, the legislative history reveals a strong current of congressional solicitude for the plight of a criminal defendant exposed to additional expense and anxiety by a government appeal and the incumbent possibility of multiple trials. Criminal appeals by the Government “always threaten to offend the policies behind the double-jeopardy prohibition,” Will v. United States, supra, at 96, even in circumstances where the Constitution itself does not bar retrial. Out of a collision between this policy concern, and the competing policy favoring review, Congress enacted a bill that fully satisfied neither the Government nor the bill’s opponents.51 For the Criminal Appeals Act, thus born of compromise, manifested a congressional policy to provide review *299in certain instances but no less a congressional policy to restrict it to the enumerated circumstances.

Were we to throw overboard the ballast provided by the statute’s language and legislative history, we would cast ourselves adrift, blind to the risks of collision with other policies that are the buoys marking the safely navigable zone of our jurisdiction. As we have shown, what the District Court did in this case cannot be distinguished from a post-verdict acquittal entered on the ground that the Government did not present evidence sufficient to prove that Sisson was insincere. A primary concern of the bill that emerged into law was that no appeal be taken by the Government from an acquittal no matter how erroneous the legal theory underlying the decision. Moreover, going beyond the present case, the theory of those in disagreement would allow a trial judge to reserve to himself the resolution of disputes concerning facts underlying a claim that in particular circumstances a speech or protest march were privileged under the First Amendment, a practice plainly inconsistent with a criminal defendant’s jury trial rights.

C

Quite apart from the arresting judgment provision, it is also argued that we have jurisdiction under the “motion in bar” provision of the Criminal Appeals Act. We think it appropriate to address ourselves to this contention, particularly in light of the fact that we asked the parties to brief that issue,52 even though our holding that the decision below was an acquittal is sufficient to dispose of the case.

*300The case law under the motion-in-bar provision is very confused,53 and this Court has not settled on a general approach to be taken in interpreting this provision.54 *301Even under the most expansive view, however, a motion in bar cannot be granted on the basis of facts that would necessarily be tried with the general issue in the case.55 In this case, there can be no doubt that the District Court based its findings on evidence presented in the trial of the general issue. As we have shown earlier, the court’s findings were based on Sisson’s testimony and demeanor at the trial itself. Moreover, a defense based on Sisson’s asserted constitutional privilege not to be required to fight in a particular war would, we think, necessarily be part of the “general issue” of a suit over a registrant’s refusal to submit to induction. As The Chief Justice says in his dissenting opinion, “establishing the appropriate classification is actually an element of the Government’s case,” post, at 324, once a defendant raises a defense challenging it. We think a defense to a pre-induction suit based on conscientious objections that require factual determinations is so intertwined with the general issue that it must be tried with the general issue, United States v. Fargas, 267 F. Supp. 462, 455 (1967) (pretrial motion to dismiss under Rule 12 (b) (1) on the basis of an affidavit, denied because “the validity of the [conscientious objector] defense which Fargas now raises . .. will require the consideration of factual questions which are embraced in the general issue”); see United States v. Ramos, 413 F. 2d 743, 744 n. 1 (C. A. 1st Cir. 1969) (evidentiary hearing for pretrial motion to dismiss indictment not appropriate means to consider validity of defense based on conscientious objection because “[questions regarding the validity of *302appellant’s classification should have been raised as a defense at the trial,” citing Fargas with approval).56

There is, in our view, still another reason no appeal can lie in this case under the motion-in-bar provision. We construe the Criminal Appeals Act as confining the *303Government’s right to appeal — except for motions in arrest of judgment — to situations in which a jury has not been impaneled, even though there are cases in which a defendant might constitutionally be retried if appeals were allowed after jeopardy had attached. Because the court below rendered its decision here after the trial began, and because that decision was not, as we have shown, an arrest of judgment, we therefore conclude there can be no appeal under the other provisions of § 3731.

*304We reach this conclusion for several reasons. Eirst, although the legislative history is far from clear, we think it was the congressional expectation that except for motions in arrest — which as we have shown could never be based on evidence adduced at trial — the rulings to which the bill related would occur before the trial began.57 The language of the motion-in-bar provision *305itself limits appeals to those granted “when the defendant has not been put in jeopardy.” We read that limitation to mean exactly what it says — i. e., no appeal from a motion in bar is to be granted after jeopardy attaches. Although the legislative history shows much disagreement and confusion concerning the meaning of the constitutional prohibition against subjecting a defendant to double jeopardy58 there was little dispute over the then-settled notion that a defendant was put into jeopardy once the jury was sworn.59 To read this limitation as no more than a restatement of the constitutional prohibition, as suggested by Mr. Justice White, renders it completely superfluous. No Senator thought that Congress had the power under the Constitution to provide for an appeal in circumstances in which that would violate the Constitution.60

Our conclusion draws strength from the fact that the Government itself has placed exactly this same interpre*306tation on the Act. The Department of Justice, the agency for whose benefit the original bill was enacted, first placed this construction on the statute shortly after the bill was enacted, and has consistently abided by it in the more than 60 years that have since passed. As the Solicitor General stated in his brief:

“The Department of Justice has consistently taken the view that the plea in bar section limits the government’s right of appeal to the granting of such pleas before a jury has been sworn. Soon after passage of the original Act, the 1907 Report of the Attorney General urged that the omission in the Act of a governmental right to appeal from post-jeopardy rulings be remedied by revising the Act so as to require counsel for the defendant to raise and argue questions of law prior to the time when jeopardy attached,” Brief 17.

Later, after describing the opinion in Zisblatt, supra, in which the Second Circuit certified an appeal to this Court to determine whether the phrase “not been put in jeopardy” merely incorporated the constitutional limitation, or instead should be taken literally, the Government’s brief states:

“The then Solicitor General, being of the view that the statute barred appeals from the granting of motions in bar after jeopardy had attached, moved to dismiss the appeal, and the appeal was dismissed (336 U. S. 934). The Department of Justice has thereafter adhered to that position, and the government has never sought to appeal in these circumstances.” 61

This interpretation in our view deserves great weight.

*307In light of (1) the compromise origins of the statute, (2) the concern with which some Senators viewed the retrial of any defendant whose trial terminated after the jury was impaneled, and (3) the interpretation placed on the Act shortly after its passage62 that has been consistently followed for more than 60 years by the Government, we think that the correct course is to construe the statute to provide a clear, easily administered test: except for decisions arresting judgment, there can be no government appeals from decisions rendered after the trial begins.

IV

Clarity is to be desired in any statute, but in matters of jurisdiction it is especially important. Otherwise the courts and the parties must expend great energy, not on the merits of dispute settlement, but on simply deciding whether a court has the power to hear a case. When judged in these terms, the Criminal Appeals Act is a failure. Born of compromise, and reflecting no coherent allocation of appellate responsibility,63 the Criminal Appeals Act proved a most unruly child that has not improved with age. The statute’s roots are grounded in pleading distinctions that existed at common law but *308which, in most instances, fail to coincide with the procedural categories of the Federal Rules of Criminal Procedure. Not only does the statute create uncertainty by its requirement that one analyze the nature of the decision of the District Court in order to determine whether it falls within the class of common-law distinctions for which an appeal is authorized,64 but it has also engendered confusion over the court to which an appeal-able decision should be brought.65

The Solicitor General, at oral argument in this case, forthrightly stated that “there are few problems which occur so frequently or present such extreme technical difficulty in the Solicitor General’s office [as] in the proper construction of the Criminal Appeals Act.”66 We share his dissatisfaction with this statute. Nevertheless, until such time as Congress decides to amend the statute, this Court must abide by the limitations imposed by this awkward and ancient Act.

We conclude that the appeal in this case must be dismissed for lack of jurisdiction. R & g0 onW-

dissenting.

Both the Government and Sisson have argued that this Court has jurisdiction to review the District Court’s *309action by virtue of the “arrest of judgment” clause in the Criminal Appeals Act, 18 U. S. C. § 3731, which provides for a direct appeal to this Court

“[f]rom a decision [1] arresting a judgment of conviction [2] for insufficiency of the indictment or information, [3] where such decision is based upon the invalidity or construction of the statute upon which the indictment or information is founded.”

In rejecting the arguments of the parties the Court holds that we have no jurisdiction to hear this appeal, opting for the view that the “arrest of judgment” clause carries with it all of its common-law antecedents and that the present case does not meet the criteria required by the common law. My disagreement with the Court’s result and rationale is prompted by a fundamental disagreement with the Court’s mode of analysis and its excessive reliance on ancient practices of common-law England long superseded by Acts of Congress.

Section 3731 appears to set three requirements for jurisdiction in this Court: (1) the decision from which the appeal is taken must be one “arresting a judgment of conviction”; (2) the decision must be engendered by the “insufficiency of the indictment or information”; and (3) it must be “based upon the invalidity or construction of the statute upon which the indictment or information is founded.”

I

The first requirement, that the decision from which the appeal is taken must be one “arresting a judgment of conviction,” can without undue violence to its language be construed as being encrusted with the lore of centuries of common-law jurisprudence, and the Court has so construed it. The form of an “arrest of judgment” was well established at an early date in the common law’s development; Blackstone was able to describe a clearly defined motion in arrest as a device that was proce*310durally appropriate after the guilty verdict had been rendered but before the judge had imposed sentence. The court, in an early form of permitting allocution, traditionally asked the prisoner if he had “anything to offer why judgment should not be awarded against him.” 4 W. Blackstone, Commentaries *375. The prisoner could then respond by offering exceptions to the indictment, “as for want of sufficient certainty .in setting forth either the person, the time, the place, or the offence.” Ibid. If the prisoner was successful, the court entered an arrest or stay of the judgment. Also, under the common law, it was settled that “the Court ought not to arrest judgments upon matters not appearing upon the face of the record; but are to judge upon the record itself, that their successors may know the grounds of their judgment.” Sutton v. Bishop, 4 Burr. 2283, 2287, 98 Eng. Rep. 191, 193 (K. B. 1769) (emphasis added). The record included “nothing more than the judgment roll; and indeed, the common-law knew nothing of the evidence taken at a trial until the Statute of Westminster allowed exceptions to be sealed and a bill of exceptions to be brought up with the roll on writ of error.” United States v. Zisblatt, 172 F. 2d 740, 741-742 (C. A.. 2d Cir.) (L. Hand, C. J.), appeal dismissed on Government’s motion, 336 U. S. 934 (1949).

Much, if not all, of the common-law learning was transplanted to the United States. As early as 1807, the Court recognized the existence of the motion in United States v. Cantril, 4 Cranch 167 (1807). And, in 1820, Chief Justice Marshall stated for the Court that “judgment can be arrested only for errors apparent on the record . . . .” United States v. Klintock, 5 Wheat. 144, 149 (1820). See also Carter v. Bennett, 16 How. 354 (1854); Bond v. Dustin, 112 U. S. 604 (1884).

Whether § 3731’s requirement of an arrest of judgment incorporates the common-law jurisprudence, or *311whether it is viewed as simply looking to the standards of Rule 34, Fed. Rules Crim. Proc.,1 the Court has indicated that it believes that the decision of the District Court here was not one “arresting a judgment” because it was based on evidence adduced at the trial, notwithstanding the precise — and I suggest, purposeful, delineations of an astute District Judge quite as familiar with history and the background of this statute as are we.

The Solicitor General also has conceded that § 3731 uses the term “arrest of judgment” in its common-law sense. However, he has sought to avoid the inescapable implications of this concession by arguing that the District Court, “in granting appellee’s motion, did not base its action wholly on the allegations of the indictment, but used as a partial predicate for its constitutional rulings the undisputed fact, which appeared from the evidence at trial, that appellee is a non-religious conscientious objector to participation in the Vietnam conflict.”2 The Solicitor General’s argument in favor of jurisdiction seeks to avoid the District Court’s reliance on evidence by pointing out that the District Court’s decision did not purport to be a judgment on the merits, %. e., that the evidence was not sufficient to show that appellee committed the offense charged, and thus was not a directed acquittal. He submits that the District Court used Sisson’s sincere, nonreligious form of conscientious *312objection to a particular war as the basis for its ruling that the indictment was constitutionally infirm as applied to Sisson. Since the evidence of conscientious objection was undisputed at trial3 and is undisputed now, the Solicitor General argues that the use of the facts here was akin to a stipulation of facts by parties in a criminal case, and that this Court has recognized that such a stipulation may be treated by the District Court as supplementing the indictment (like a bill of particulars) . He relies on United States v. Halseth, 342 U. S. 277 (1952), and United States v. Fruehauf, 365 U. S. 146 (1961).4

*313My disagreement with the Court is based upon much more fundamental grounds than those which the Solicitor General would use to avoid the strictures of the common-law concept of an arrest of judgment. In my view the Criminal Appeals Act contemplates that an arrest of judgment is appropriate in other than a closed category of cases defined by legal history. Specifically, there is no reason for the Court today to read into that *314class of cases all of the niceties of what might or might not have been included in the “judgment roll” at common law. We have outgrown those formalisms.

I conclude that evidence adduced at trial can be considered by a district court as the basis for a motion in arrest of judgment when that evidence is used solely for the purpose of testing the constitutionality of the charging statute as applied. I do so because the legislative history surrounding the passage of the Criminal Appeals Act abundantly shows Congress contemplated review by this Court in such a case. The reasons for the Court’s face-of-the-record limitation, in the technical common-law form of an arrest of judgment, have long since disappeared, and the Court’s reliance on a policy disfavoring appeals under the Criminal Appeals Act is misplaced.

The Court’s reasoning pays scant attention to the purpose of the Criminal Appeals Act and to the problem that Congress was attempting to solve in 1907 when the Act was passed. The legislative history of the Criminal Appeals Act reflects the strong desire by a number of Attorneys General of the United States for an appellate remedy in selected criminal cases.5 Such a remedy had been provided in England and in some States, but the lack of such a remedy for the Federal Government had “left all federal criminal legislation at the mercy of single judges in the district and circuit courts. This defect became all the more serious because it became operative just at the beginning of the movement for increasing social control through criminal machinery.” 6 Congress, however, was not stirred to complete its action on the *315proposals until a federal district court rendered its decision in United States v. Armour & Co., 142 F. 808 (D. C. N. D. Ill. 1906), sustaining a motion to dismiss and ending a Sherman Act prosecution in which President Theodore Roosevelt had a great interest.

The House passed, without debate, a bill that gave the United States in all criminal prosecutions “the same right of review by writ of error that is given to the defendant,” provided that the defendant not twice be put in jeopardy for the same offense. 40 Cong. Rec. 5408 (1906). The Senate, however, refused to accept the House bill. Rather, its Judiciary Committee offered as a substitute a more complicated bill which ultimately was refined to become the Criminal Appeals Act. In relevant part, the substitute would have allowed a writ of error by the United States “[f]rom the decision arresting a judgment of conviction for insufficiency of the indictment.” S. Rep. No. 3922, 59th Cong., 1st Sess. (1906). When the substitute came to the floor of the Senate, the floor leader for the bill, Senator Knute Nelson of Minnesota, explained the need for the legislation in constitutional terms: “[SJometimes an indictment is set aside on the ground that the law under which the indictment was found is held to be unconstitutional. The object [of this bill] is to allow the Government to take the case up and get a ruling of the Supreme Court.” 40 Cong. Rec. 8695 (1906) (emphasis added). The bill was then put over in the absence of unanimous consent for consideration. When the bill returned to the floor, questions were raised with respect to the arrest of judgment provision regarding the prohibition against double jeopardy. Unanimous consent to proceed again was withdrawn and the bill was again put over. 40 Cong. Rec. 9033 (1906).

An amended bill was reported out of committee in January of 1907. When this bill reached the floor, a *316spirited three-day debate took place respecting its impact on an accused. Indeed, among the questions discussed was whether a defendant who succeeded on a motion in arrest of judgment could again be prosecuted. See 41 Cong. Rec. 2192-2193 (1907). But almost none of the debate concerned the scope of an “arrest of judgment.” Senator Knox, who had been the Attorney General before going to the Senate, did say that “this legislation is along the line of the law as it is understood in England under the common law.” 41 Cong. Rec. 2751 (1907). However, this statement apparently referred to the right of the Government to appeal, for it was immediately followed by the observation: “In England the Crown always had the right to an appeal in a criminal case. In my own State since its foundation the right has been conceded.” Ibid. The manifest, overriding concern of the Senate was with enacting legislation that would permit appeals as to important legal questions always subject to the bar against double jeopardy,7 and this concern carried over to the arrest of judgment provision.8 Indeed, the major limiting amendment adopted by the Senate restricted the right of review by the Government in criminal cases to constitutional issues and questions of construction of the statute under which the charge was brought. See 41 Cong. Rec. 2819-2820 (1907).

*317Another illustration of what the Senate thought it was doing in describing this category of appeals comes from the emphasis on distinguishing a “motion in arrest” from an “acquittal.” See 41 Cong. Rec. 2748 (1907). From the latter, to be sure, there was to be no appeal — no matter how many errors the trial judge had committed along the way to the acquittal in the form of erroneous rulings or other trial errors. As the majority has noted, an amendment was adopted which required that verdicts in favor of the defendant could not be set aside on appeal. 41 Cong. Rec. 2819 (1907). The text of the amendment as adopted read: “Provided, That if upon appeal or writ of error it shall be found that there was error in the rulings of the court during the trial, a verdict in favor of the defendant shall not be set aside.” Ibid. The proponent of the amendment, Senator Ray-ner, expressed the view that the amendment was directed toward a “verdict of not guilty, whether by the court or the jury . . . .” 41 Cong. Rec. 2747 (1907) (emphasis added). Here, of course, Sisson was not acquitted but was found guilty by the jury. Further, the Court’s use of the Rayner amendment to support a narrow reading of the “arrest of judgment” provision is incongruous in the extreme in light of the fact that the amendment had no substantive effect and was later deleted from the Act. See Mr. Justice White’s opinion, post, at 344 n. 11.

“Trial errors” respecting the fact-finding function— which affect only the particular trial — were distinguished from errors of law that had been separated from the trial on the merits, and that involved constitutional rulings that could affect future attempts of the Government to prosecute under the same statute:

“The defendant gets the benefit of all errors in the trial which are in his favor, and can challenge all errors in the trial which are against him. It is *318certainly not too much when he attacks the trial itself or the law under which it is conducted to give the people the right to a decision of their highest courts upon the validity of statutes made for their protection against crime.” 41 Cong. Rec. 2752 (1907) (remarks of Senator Knox).

“The motion in arrest of judgment can only be made — it is wholly inapplicable to any other condition than that of conviction — to a verdict of guilty. It is interposed after a verdict of guilty and before judgment for an alleged legal reason that will arrest the court in pronouncing judgment upon the verdict.” 41 Cong. Rec. 2753 (1907) (remarks of Senator Patterson).

The Senate passed the bill with the acquired floor amendments on February 13, 1907. 41 Cong. Rec. 2825 (1907). The House insisted on a conference, but the conference committee adopted the Senate version. The resulting conference committee bill was ultimately adopted. 41 Cong. Rec. 3994, 4128 (1907).

Notably, the debates on the Senate bill which formed the basis of the Act demonstrate a total lack of concern with the technical niceties of ancient common-law forms of pleading. And, far from distinguishing cases where a congressional act was invalidated on its face from cases where it was invalidated as applied to a situation that Congress clearly intended to reach, the debates appear to contemplate both cases as appropriate for appeal to this Court — certainly the evil aimed at — and the rationale of the Act is broad enough to encompass both situations. Appeal was to be for the purpose of deciding “constitutional questions,” “questions of law” which, if the district judge’s decision were permitted to stand, could lead to conflict and different treatment under the same *319criminal statutes in different parts of the country, with no opportunity under existing law for resolution in this Court. The Government was to have a chance to “settle the law as to future cases of like character.” 41 Cong. Rec. 2194 (1907) (emphasis added).

It is difficult to imagine a case more closely fitting into this rationale than that now before us. The class of nonreligious conscientious objectors is not likely to be a small one. Indeed under the impetus of this holding it is likely to grow. Yet whether or not a member of that class can constitutionally be punished for refusing to submit to induction now depends on where that person is tried and by whom. That one district judge may entertain a different view of the Constitution than does another is an extraordinary reason for differing results in cases that rationally ought to be decided the same way — and with appellate review available to insure that end. The conclusion that this is not a “motion in arrest,” insulates the judge’s constitutional decision from review anywhere — here or in the Court of Appeals. That, I submit, is precisely the situation Congress thought it was correcting with the Criminal Appeals Act. It is remarkable that the Court finds it so easy to ignore the explicit and meaningful legislative history which refutes its strained reading of the statute and history.

The common-law rule that an arrest of judgment could be based on nothing more than the judgment roll seems to have been required by the existence of the very limited record of that day which did not include the evidence adduced at trial. Evidentiary matters were not before the appellate courts, and it would have been impossible for the arresting court’s “successors [to] know the grounds of their judgment,” Sutton v. Bishop, supra, if the arresting court considered the evidence at trial. This *320Court in this case obviously has no such problem in providing appellate review. The records before us contain complete transcripts of the trial proceedings as a matter of course.

Accordingly, while the District Court admittedly looked to evidence, including demeanor evidence, for its findings that Sisson was “sincere” and was “genuinely and profoundly governed by his conscience,” this use for that purpose should not now bar this Court from considering the District Court’s action as an arrest of judgment. As long as the evidence was used to test the constitutionality of the charging statute as applied to the defendant, and not to test the sufficiency of the proof against the allegations in the indictment, the use of the evidence was consistent with the purposes of an arrest of judgment.

In this case, there has been no finding that Sisson did not commit the acts charged; there has been only a holding by the trial judge that his acts were constitutionally protected — a holding that stands as the sole impediment to imposing a jury verdict of guilty; no verdict of acquittal was ever returned. Even our present Federal Rules of Criminal Procedure make a similar distinction between a “Motion for Judgment of Acquittal,” Rule 29, and an “Arrest of Judgment,” Rule 34. The former is entered “if the evidence is insufficient to sustain a conviction” of the offense charged, while the latter is granted where the indictment “does not charge an offense” at all. Rule 29 allows a judge to reserve his decision on a motion for judgment of acquittal until after the jury has returned a verdict. If he then grants the motion, the defendant stands acquitted, but again only because the evidence has been found insufficient to support the charge. Where the grounds for granting an “acquittal” are based on an independent legal deci*321sion about the interpretation or construction of the statute, the judge’s action will be an “arrest of judgment” even though he labels it an “acquittal.” United States v. Waters, 84 U. S. App. D. C. 127, 175 F. 2d 340 (1948).

I cannot believe that Congress, fully aware that no appeal was available for a directed verdict or judgment n. o. v., contemplated that this form of judicial action should be accorded the same nonappealable status. Moreover, the sophisticated District Judge could have entered a judgment n. o. v. if he wanted to avoid review or if he thought that he was indeed passing on the sufficiency of the evidence to meet the allegations of the indictment. Of course, his views are not controlling, but I am comforted by his appraisal and quite satisfied he knew precisely what he was doing — or thought he did on the assumption that his action was reviewable under well-established principles the Court now ignores.

The Court also inveighs against a “broad” construction of the Act, noting that this Court has denominated an appeal by the Government in a criminal case as an “exceptional right,” and as “something unusual, exceptional, not favored.” Ante, at 291. This is an odd characterization; the right is precisely as “exceptional” or “unusual” as Congress makes it. This Court has no power to define the scope of its own appellate review in this context and a subjective distaste for review at the instance of government has no proper place in adjudication. The tendency to be miserly with our jurisdiction did not prevent our construing the three-judge court acts to include cases where statutes were held unconstitutional as applied, Query v. United States, 316 U. S. 486 (1942); C. Wright, Federal Courts 190 (2d ed., 1970), and it should not carry any more weight in assessing our responsibility to decide the constitutional issues in this *322case,9 the more so when it is a constitutional holding of great moment.

II

The second requirement, that the decision of the District Court must rest upon the “insufficiency of "the indictment,” also presents a difficult question here. The Court emphasizes, wrongly, in my view, that both grounds upon which the District Court’s decision rests are defenses that Sisson successfully asserted. In an ordinary case, an indictment, to be sufficient, need not anticipate affirmative defenses. This, however, is not’ the ordinary case. The indictments ,in cases of this nature typically charge only that the Selective Service registrant

“did unlawfully, knowingly and wilfully fail and neglect and refuse to perform a duty required of him under and in the execution of the Military *323Selective Service Act of 1967 and the rules, regulations and directions duly made pursuant thereto, particularly 32 Code of Federal Regulations 1632.14, in that he did fail and neglect and refuse to comply with an order of his local draft board to submit to induction into the armed forces of the United States; in violation of Title 50, Appendix, United States Code, Section 462.”10

Yet this allegation subsumes in its terse language a myriad of elements that the Government may be called upon to prove if the defense makes an appropriate challenge. Prosecutions for refusing to submit to induction are unusual because they incorporate into the judicial proceeding m,uch that has occurred in the administrative processes of the Selective Service System. All of the courts of appeals have compensated for the administrative proceedings by holding that the Government need not plead and prove many elements that would normally be a part of its case-in-chief. The courts of appeals have devised a presumption of regularity which attaches to the official acts of the local boards that, standing alone, is sufficient to preclude reversal of a conviction when a given element is not raised at trial. See particularly Yates v. United States, 404 F. 2d 462 (C. A. 1st Cir. 1968) (presumption of regularity attaches to the order-of-call requirement). However, if the defendant succeeds in making a prima facie case against the presumption, the Government is put to its proof on the particular element of the offense. See United States v. Baker, 416 F. 2d 202 (C. A. 9th Cir. 1969).

By analogy, the Government is not required to plead and prove that the defendant was properly classified in category I-A as available for induction. Rather, the *324defendant can challenge the classification at trial if he has preserved his claim, and force the Government to prove that there was indeed a “basis in fact” for the classification. Thus, establishing the appropriate classification is actually an element of the Government’s case, but because of the deference given to the administrative process that preceded the criminal proceedings, the Government has been excused from pleading and proving it in the indictment. Since the general allegations in the indictment actually do subsume the element that the District Court held was based on an invalid statute as applied to Sisson, that court’s decision was based on the “insufficiency of the indictment” within the meaning of § 3731.

The Court also appears to assume that an indictment may be “insufficient” because the acts charged cannot constitutionally be made an offense, e. g., where they show the existence of a constitutional privilege that bars conviction. But, the Court concludes that “this indictment . . . does not allege facts that themselves demonstrate the availability of a constitutional privilege.” Ante, at 288.

In my view, the Court’s suggestion is simply the same argument, differently approached, as the argument that a motion in arrest can be based only on facts appearing on the face of the record. In both cases, the single question, as I see it, is whether Congress drew a distinction for purposes of appeal by the Government, between cases in which the district court found the entire statute unconstitutional, and cases .in which the court found the statute unconstitutional as applied.

The view has been expressed that the Criminal Appeals Act is badly drawn and gives rise to a multitude of problems. We can all agree as to the infirmities of the statute but this is hardly an excuse to take liberties with its plain purposes reasonably articulated in its terms. Prior *325urgings addressed to the Congress to correct this situation have gone unheeded. But the Court’s holding today is a powerful argument to spur corrective action by Congress.

dissenting.

I

I agree with The Chief Justice that this case can be appealed by the Government under the “motion in arrest” provision of the Criminal Appeals Act. In contrast to the rather clear remedial purpose of the Act, not a single passage in the legislative history indicates awareness by Congress that the words it was using had the effect of distinguishing cases where a congressional Act was held invalid on its face from cases where it was invalidated as applied to a sub-class within the Act’s intended reach. In both cases, the indictment is “insufficient” to state a valid offense.1 In both cases, any “factual findings” necessary to give the particular defendant the benefit of the constitutional ruling are little more than findings as to the defendant’s standing to raise the constitutional issue — they are not findings as to the sufficiency of the evidence to prove the offense alleged in the indictment.2 Thus, if Judge Wyzanski, without making any findings as to Sisson’s sincerity, had held *326the Selective Service Act unconstitutionally overbroad because it purported to subject to the draft in violation of the Free Exercise Clause sincere, nonreligious objectors, this Court would clearly have jurisdiction and would face the question whether Sisson could raise the claim without showing that he was a member of the allegedly protected class. Cf. Thornhill v. Alabama, 310 U. S. 88 (1940). If such a showing had to be made, as the judge here held it did, the question of standing and the facts relevant to that question are surely distinct from the question of whether the defendant committed the offense, or the question of the validity vel non of the statute.3 Cf. Association of Data Processing Service Organizations v. Camp, 397 U. S. 150 (1970); Barlow v. Collins, 397 U. S. 159 (1970).

II

We asked the parties in this case to consider whether 18 U. S. C. § 3731 confers jurisdiction on the ground that the lower court had sustained “a motion in bar, when the defendant has not been put in jeopardy.” The majority, after a lengthy discussion of the “motion in arrest” provision, condescends to address a few remarks to this question, with the suggestion that it really need not discuss the issue at all, since .it has concluded that Judge Wyzanski’s action amounted to “an acquittal.” As Mr. *327Justice Black’s concurrence .indicates, the lengthy discussion of the “motion in arrest” provision is equally superfluous if indeed it is so clear that Sisson has been “acquitted.” In reality, the bald assertion that Sisson has been “acquitted” simply begs the matter at issue: until one knows what a “motion in bar” is, as well as a “motion in arrest,” and how the granting of such motions differs from granting a judgment of acquittal, one cannot confidently attach any label to Judge Wyzanski’s action.

The only reason the majority gives for concluding that Sisson has been acquitted is based, not on what actually happened, but on what might have happened. Since Judge Wyzanski could have submitted the case to the jury on instructions reflecting his view of the law, and since the jury so instructed could have returned a verdict of “not guilty,” therefore we must pretend that that is what has actually happened. That suggestion is nonsense. One does not determine “what in legal effect [Judge Wyzanski’s decision] actually was,” ante, at 279 n. 7, by asking “what in legal effect the decision might have been.” If that were the key question, then this Court should not have had jurisdiction in United States v. Covington, 395 U. S. 57 (1969) (Harlan, J.). There the trial judge accepted the defendant’s argument that the Fifth Amendment prevented the Marihuana Tax Act from constitutionally being applied to him. Under the majority’s view, that action would amount to an acquittal because the judge might have given the case to the jury under instructions that it should acquit if it found the facts necessary to sustain the defendant’s privilege — e. g., that he was not one of the registered marihuana dealers whose conduct was legal under state law. Indeed, if applied consistently the majority’s theory would mean that there is no case that could be appealed to this Court under the *328“motion in bar” provision of the Criminal Appeals Act. For it will always be true that a judge might have sent the case to the jury under instructions reflecting his view that the motion in bar was good, so that if the jury found the facts relied on in the motion, it should acquit.4

*329The difference between “what might have been” and what actually happened .in this case is large and critical. Where the jury actually “acquits” under an erroneous instruction, a successful appeal leading to reversal and a new trial would raise serious constitutional problems by placing the defendant through the hazards of another trial for the same offense. In this case, however, there is no possibility of subjecting Sisson to another trial, or of overturning a factfinder’s decision that, whatever the law, Sisson should go free. If Judge Wyzanski’s legal theory is incorrect, the jury’s verdict of guilty— with judgment no longer “arrested” — simply remains in effect.

It was precisely this distinction that Senator Knox was referring to in the passage quoted in the majority opinion, ante, at 289: the defendant retains the benefit of any error whatever committed by the court “in the trial”; but the Government gets an appeal “upon ques*330tions of law raised by the defendant to defeat the trial.” The distinction is also reflected in the majority’s quotation from United States v. Ball, ante, at 289-290, where the question of what constitutes an “acquittal” is tied to the question of whether the defendant would be put “twice in jeopardy” by an appeal.

I suspect that the Court’s reluctance to discuss the “motion in bar” provision and to distinguish the granting of such motions from an acquittal stems from the fact that, unlike the “motion in arrest,” there .is no doubt that a “motion in bar” properly sets forth an affirmative defense, which necessarily requires resort to facts not found in the indictment or on the face of the “record.” Thus most of the majority’s argument that this case is not appealable as a “motion in arrest” because “[t]he decision below rests on affirmative defenses,” ante, at 287-288, is simply irrelevant as far as the “motion in bar” is concerned.

In fact, as the majority seems to concede by its reluctance to reject square precedent on the issue, see ante, at 300 n. 53, our cases make clear that the phrase “motion in bar” would include a plea like Sisson’s that the selective service laws are unconstitutional as applied to him. The Court has never adopted the view that a “motion in bar” encompasses only the common-law defenses of autrefois acquit, autrefois convict, and pardon.5 Neither did Congress when it passed the Act. The debates show that the plea in bar was thought to embrace such a variety of defenses as the statute of limitations, e. g., 41 Cong Rec. 2749, and a plea of Fifth Amendment *331immunity, see 41 Cong. Rec. 2753. The most thorough discussion of the “motion in bar” in this Court occurs in the concurring and dissenting opinions in United States v. Mersky, 361 U. S. 431 (1960). Mr. Justice Brennan argued that a motion in bar would encompass every possible affirmative defense that would prevent retrial. Mr. Justice Stewart argued for a narrower interpretation, similar to the concept of a plea in confession and avoidance, i. e., a plea that “did not contest the facts alleged in the declaration, but relied on new matter which would deprive those facts of their ordinary legal effect.” Id., at 457.

Even under the narrower interpretation of Mr. Justice Stewart, Sisson’s plea qualifies as a “motion in bar.” For as the majority’s opinion makes clear, the crux of the case against Sisson was simply whether or not he had wilfully refused to submit to induction; the question of his sincerity was “new matter” relied on to deprive the fact of his wilfull refusal of its ordinary legal effect. See majority opinion, ante, at 276; United States v. Blue, 384 U. S. 251, 254 (1966) (Harlan, J.). Just as our cases have permitted the “motion in bar” to embrace limitations pleas, see, e. g., United States v. Goldman, 277 U. S. 229 (1928), and pleas of constitutional privilege, see United States v. Murdock, 284 U. S. 141 (1931), so too they permit the “motion in bar” to reach cases of this sort, attacking the validity of the statute as applied to the defendant. See United States v. Covington, 395 U. S. 57 (1969) (Harlan, J.); United States v. Blue, supra, at 254 (Harlan, J.).

Procedurally, the fact that the plea is sustained only after a jury verdict of conviction — and the fact that the judge labeled his action as something other than a “motion in bar” — does not prevent finding a “motion in bar.” United States v. Zisblatt, 172 F. 2d 740, 742 (C. A. 2d Cir.), appeal dismissed, 336 U. S. 934 (1949). Even *332the legislative history recognizes that such pleas could be sustained after the trial had begun. 41 Cong. Rec. 2749 (remarks of Senator Rayner). Nor is there any doubt — unlike the case of a motion in arrest— that a proper motion in bar results even though factual issues relevant to the motion have to be tried. See 41 Cong. Rec. 2194 (remarks of Senator Whyte); id., at 2753 (remarks of Senator Patterson); United States v. Zisblatt, supra. Indeed, Mb. Justice Harlan recently referred to the possibility of trying facts to the judge that were relevant to the motion in bar, and separate from the general issue. See United States v. Covington, supra, at 60. In his words, “[a] defense is thus 'capable of determination’ [without trial of the general issue] if trial of the facts surrounding the commission of the alleged offense would be of no assistance in determining the validity of the defense.” Ibid. That description fits this case precisely since, as already noted, the majority itself takes careful pains to point out that the “general issue” — whether Sisson wilfully refused induction — was at all times separate from the issue raised by Sisson’s constitutional claim.6

*333This case, then, is indistinguishable as far as the “motion in bar” provision is concerned from United States v. Zisblatt, supra, which the majority cites with approval throughout its opinion. There, as here, the de*334fendant moved for dismissal of the indictment on the basis of an affirmative defense — in that case the statute of limitations. There, as here, the judge reserved ruling on the motion until after the jury had returned a verdict of guilty. There, as here, the judge then granted the defendant’s motion, relying on matters “outside the record.” The Government appealed to the Court of Appeals, where the question became whether or not the appeal should have been taken directly to this Court under the Criminal Appeals Act. Judge Learned Hand, in deciding that the trial court’s action amounted to sustaining a motion in bar, made short shrift of the argument that the case was indistinguishable from the case of a directed verdict of acquittal.

“Had the trial judge directed a verdict, so that it would have been necessary upon reversal to subject the defendant to trial before a second jury, that' would be ‘double jeopardy,’ but, although the Constitution gives an accused person the benefit of any mistakes in his favor of the first jury he encounters, whether it has passed upon his guilt or not, it does not extend that privilege to mistakes in his favor by judges. Indeed, were the opposite true, all appeals from decisions in arrest of judgment would be constitutionally futile because no judgment of conviction could be entered when they were reversed.” 172 F. 2d, at 743.

*335The sole question, then, in this case as in Zisblatt, is whether the defendant has been “put in jeopardy” as that phrase is used in the Criminal Appeals Act. That question in turn centers on whether the phrase is to be read literally, in which case a defendant would be in jeopardy as soon as a jury was .impaneled, or whether the phrase is to mean “constitutional” or “legal” jeopardy, in the sense that even if the Government were to succeed on appeal, it would be unable to take advantage of its success in new proceedings against the defendant. Although the Government has chosen to read the statute in the former, literal sense, this Court has never resolved the issue. Judge Learned Hand thought there was a “more than plausible argument” for the latter, “legal jeopardy” view, but the Government dismissed its appeal to this Court before the question could be decided. United States v. Zisblatt, supra, at 742.

The legislative history of the 1907 Act unmistakably shows that Congress meant to allow the Government an appeal from a decision sustaining a motion in bar .in every case except where the defendant was entitled to the protection of the constitutional guarantee against double jeopardy. I find the debates so convincing on that point that I am at a loss to understand why the Government has so readily conceded the issue unless it be to maintain the appearance of consistency, and to protect its interests ,in securing new criminal appeals legislation before Congress.7 Certainly that concession *336does not bind this Court;8 even more certainly it is no excuse for the majority’s failure to conduct its own examination of the relevant debates.

Out of three full days of debate in the Senate, covering more than 30 pages of the Congressional Record, see 41 Cong. Rec. 2190-2197, 2744-2763, 2818-2825, the majority finds a total of three passages to cite in a footnote as support for its interpretation, see ante, at 304-305, n. 57. In each case, the statements placed in context prove just the opposite of the majority’s conclusion. The first reference, to a passage before debate even began, 40 Cong. Rec. 9033, is to Senator Spooner’s *337question whether the bill applied only to questions arising before the impaneling of the jury. As the majority acknowledges, Senator Nelson immediately corrected Senator Spooner, pointing out that the key question was “jeopardy,” not the impaneling of the jury. The entire brief exchange occurred before the bill was debated, further consideration having immediately been postponed by the objection of other Senators to pursuing the matter at that time. See F. Frankfurter & J. Landis, The Business of the Supreme Court 117 n. 68 (1928). When debate was resumed at the next session of Congress, Senator Spooner unmistakably indicated that jeopardy was being used in the constitutional, legal sense, in direct opposition to the views the majority now tries to ascribe to him:

“The question is whether it subjects a man under any aspect of it to the danger of double jeopardy.

I am content to leave it, under the bill, if it shall become a law, to the Supreme Court of the United States. It is their function to determine what is jeopardy. It is their function to protect the citizens of the United States against any invasion of the constitutional guaranty as to double jeopardy. I think we can rely upon the court to protect as far as the Constitution requires it all defendants . . . .” 41 Cong. Rec. 2762-2763 (remarks of Sen. Spooner).

In the second passage, 41 Cong. Rec. 2191, the majority quotes Senator Nelson for the proposition that-no appeal would lie where a jury had been impaneled. The actual quotation is that no appeal would lie “where a jury has been impaneled and where the defendant has been tried . . . 41 Cong. Rec. 2191 (emphasis added). In context, it is clear that Senator Nelson is venturing an interpretation of “jeopardy” in the legal sense. The whole dispute at this point in the debate is *338primarily between Senator Rayner who opposed the bill, and Senators Bacon and Nelson, who supported the bill. The proponents were at pains to show that a person could not be “put twice in jeopardy” under any of the provisions of the bill, 41 Cong. Rec. 2193 (remarks of Sen. McCumber; remarks of Sen. Bacon). Senator Rayner was intent on showing how difficult it was for anyone to give an adequate definition of just what “legal jeopardy” is — he supported a return to the House suggestion, which would have given the defendant the benefit of his favorable decision whether or not he had been “put in jeopardy.” But not a single passage can be cited to show that either side had the slightest inkling that “jeopardy” was being used in any but its technical, legal sense as interpreted by this Court and state courts. That was the whole point of Senator Rayner’s objection: “jeopardy” was too vague a term, because nobody could decide exactly when constitutional jeopardy had attached. How the majority can rely on Senator Nelson for the conclusion that “jeopardy” means “literal” jeopardy is particularly difficult to understand, given the Senator’s own unambiguous explanation that as author of the bill, what he meant was “constitutional” jeopardy:

“I aimed to put the bill in such a form that it would cover exactly those cases in which the defendant had not been put in jeopardy under the Constitution of the United States. I believe that the bill is limited strictly to that matter.” 41 Cong. Rec. 2757 (emphasis added).

Senator Bacon during this same exchange noted that the “jeopardy” provisions had been put in “out of abundance of caution,” 41 Cong. Rec. 2191. He proceeded to explain by his remarks that he meant precisely what the majority today declares he could not have meant— namely, that Congress was simply emphasizing that it was not attempting to subject a defendant to constitu*339tional double jeopardy by a successful government appeal. In fact, when one of the Senators asked whether “jeopardy” was to be taken in a possibly literal sense, Senator Bacon hastened to reply:

“That is not what the law means by being put in jeopardy at all. The words ‘being in jeopardy’ are entirely a technical phrase, which does not relate to the fact that a man is in danger as soon as an indictment is preferred against him.” 41 Cong. Rec. 2191 (emphasis added).

It is hardly “superfluous” for Congress to guard against a construction of an Act that might render the Act unconstitutional. And the fact that the majority would have written the statute differently to avoid what it calls a “superfluous” reading, is no excuse for ignoring the explicit indication that that is exactly the reading that Congress meant the phrase to bear.9

*340The majority’s final passage refers to a remark by Senator Patterson suggesting that a motion in arrest was the only provision under the bill that could be raised after a trial had begun. As the majority concedes, one need only read on a bit further to discover that Senator Patterson immediately retracted that suggestion when challenged, insisting that a “motion in bar” could also be granted after trial had begun and that an appeal would lie as long as no problem of “constitutional jeopardy” was presented. Indeed, Senator Patterson argued vigorously that there would have been jurisdiction in the Beef Trust Case — a case in which the motion in bar was not only granted after trial had begun, but was also reflected in the judge’s instructions to the jury. Senator Patterson’s remarks are particularly interesting because, apart from whether he is right on the question of constitutional jeopardy, he makes clear the distinction between a motion in bar and an acquittal which the majority blithely ignores:

“A special plea in bar ... is a plea that does not relate to the guilt or innocence of the defendant in the sense as to whether he did or not commit the act for which he was indicted. A special plea in bar is that which is set up as a special defense notwithstanding the defendant may be guilty of the offenses with which he is charged; it is for some outside matter; yet it may have been connected with the case. The special plea in bar that was filed by the indicted Chicago packers is a very good illustration of that. Their plea in bar set forth the fact of their having been induced or led, whatever it may have been, to make communications to the *341law officers of the Government with reference to their business that gave the district attorney information which enabled him to bring about the indictments and to help in their prosecution. That had no reference to the guilt or innocence of the accused. It was a pleading of fact that was independent of the crime for which those packers had been indicted.

“Therefore, Mr. President, there could be no jeopardy in a case of that kind where there was a decision upon the special plea in bar, because it is not under a plea of guilty or not guilty that the insufficiency of a special plea in bar is determined; it is non obstante whether the defendant is guilty or not guilty.” 41 Cong. Rec. 2753.

It is obvious from these remarks that Senator Patterson did not think that the question of “jeopardy” under the motion-in-bar provision was simply a question of whether the jury had been impaneled.10

This interpretation is made doubly clear by the remarks of Senator Nelson, the leading proponent of the bill. He also addressed himself to the Beef Trust Case and, unlike Senator Patterson, he suggested that that case could not have been appealed under the Act. But the reason he gave for that conclusion was not that the jury had been impaneled, but that the jury had been impaneled and had returned a verdict of not guilty under the judge’s instructions, thus placing the defendants in “legal jeopardy”:

“In that case a jury was impaneled, and the question whether the defendants were entitled to im*342munity under the immunity law because they had furnished Mr. Garfield and the officials of his Bureau information was submitted to the jury, and the jury under instructions of the court found for the defendants. In that case the defendants under the Constitution had been in jeopardy and in that beef-trust case no appeal could lie.” 41 Cong. Rec. 2757 (emphasis added).

See 41 Cong. Rec. 2750 (remarks of Senator Nelson).

Senator Nelson was thus talking about the majority’s “might have been case” — the case where the judge gives the motion in bar issue to the jury under his novel view of the law, so that a successful government appeal would require retrying the defendant. In the immediately following passage, Senator Nelson makes clear that if the facts pleaded in the special issue are not submitted to the jury, but tried to the judge, there would be no bar to taking an appeal. But in both cases, Senator Nelson, like Senator Patterson, is quite obviously giving his views as to what “constitutional jeopardy” means.

While the debates are replete with other indications that Congress’ concern was with “double jeopardy,” not “literal jeopardy,” the clearest such indication occurs in this very exchange between Senator Rayner, who announced his opposition to the bill in any form, 41 Cong. Rec. 2745, and Senators Spooner, Patterson, and Nelson — proponents of the bill. The exchange occupied most of the second day of the three days of debate in the Senate and centered almost entirely on Senator Rayner’s proposed amendment. The example that Senator Ray-ner used to illustrate the difficulties he saw in the bill was a hypothetical case in which a plea in bar — a limitations plea — -was sustained halfway through the trial. See 41 Cong. Rec. 2749. In that case, Senator Rayner argued, no one could say with certainty whether the de*343fendant had been put in jeopardy, and hence whether he could constitutionally be retried if the Government’s appeal were successful. Senator Rayner did not want to leave the defendant’s fate to depend on “this howling wilderness of confusion upon the subject of what constitutes legal jeopardy.” 41 Cong. Rec. 2750 (emphasis added). His amendment would thus have guaranteed that a defendant could never be retried — whatever the ultimate resolution of the “legal jeopardy” question. Those who opposed the amendment argued that if it had any substantive effect, it would make the question on any appeal “moot”; that it was enough to make sure that the Government was not allowed to secure a reversal and proceed again where the result would place the defendant in “double jeopardy”; and that the bill would leave to the Supreme Court the question of what is “jeopardy,” and hence protection “against any invasion of the constitutional guaranty as to double jeopardy.” 41 Cong. Rec. 2761-2763; see also 41 Cong. Rec. 2193. But it is clear — indeed it was again crucial to Senator Rayner’s argument — that the Senators assumed that “jeopardy” was being used in the legal sense:

“The question is whether it subjects a man under any aspect of it to the danger of double jeopardy.

“The Senator [Rayner] says he does not care whether it is double jeopardy or not. Even if a man under the Constitution may properly and lawfully be put on trial again, if he has been tried once, even though it were a mistrial, if he had been for a moment in jeopardy, he insists that we shall provide by law, no matter what the case may be, that he shall not be tried again; that he shall go acquit.

“The matter has been thoroughly argued. I am content to leave it, under the bill, if it shall be*344come a law, to the Supreme Court of the United States. It is their function to determine what is jeopardy. It is their function to protect the citizens of the United States against any invasion of the constitutional guaranty as to double jeopardy. I think we can rely upon the court to protect as far as the Constitution requires it all defendants, without supplementing the Constitution by the Senator's amendment to this bill.” 41 Cong. Rec. 2762-2763 (remarks of Senator Spooner).11

Senator Rayner’s hypothetical example of a plea in bar sustained after trial had begun — an example accepted without question by Senators Patterson, Nelson, and *345Spooner, and every other Senator participating in the debate — completely undercuts the majority’s assertion that Congress thought there could be no appeal once the jury had been impaneled. Indeed, in the face of the arguments over the meaning of “jeopardy” and Senator Rayner’s vigorous attack on the vagueness of that term, it is nothing short of incredible for the majority to suggest that Congress left that language in the Act, intending it to be interpreted as providing “'a clear, easily administered test,” ante, at 307. If Congress had intended the majority’s interpretation it would have been both simple and logical to explicitly limit appeals to cases “where the jury has not yet been impaneled,” thus avoiding the possibility of confusion which had been the very topic of discussion for three full days of debate.

The plain fact of the matter is that the majority’s post hoc rationalization of the Act simply was not that of Congress. While the debates show considerable disagreement about the meaning of “jeopardy” in the legal sense, there is not the slightest suggestion anywhere in the legislative history that “jeopardy” is being used in any other sense. Even where references occur to the impaneling of the jury as the moment when jeopardy attaches, it is clear that jeopardy is still being used in its legal sense — after all, as the majority itself notes, ante, at 305, the impaneling of the jury does in fact often become the constitutionally relevant point in determining that “legal jeopardy” has attached to prevent a reprosecution. But the one point on which there was unanimous agreement — even from Senator Rayner, see, e. g., 41 Cong. Rec. 2748 — about the meaning of “jeopardy,” was that where a convicted defendant on his own motion had secured the arrest of a jury’s verdict of guilty, he had not been placed in “jeopardy.” “[T]he defendant could not complain, either if the judgment of the court shall be entered upon the verdict or a new trial *346shall be ordered, because it is giving to the defendant a new opportunity to go acquit when, under the trial that was had, he had been convicted.” 41 Cong. Rec. 2753.

For this Court to hold that Sisson has been placed in jeopardy under the motion-in-bar provisions, thus defeating jurisdiction, the Court must be prepared to hold that a successful appeal by the Government, resulting in an order that judgment be entered on the verdict, would violate Sisson’s double jeopardy protection. Judge Learned Hand refused even to consider such a suggestion in Zisblatt: “So long as the verdict of guilty remains as a datum, the correction of errors of law in attaching the proper legal consequences to it [does] not trench upon the constitutional prohibition.” 172 F. 2d, at 743.

Ill

I find extremely peculiar the path that the Court follows in reaching its conclusion that we cannot hear this case. The “motion in arrest” provision is confined to its early common-law sense, although there is absolutely no indication that Congress was using the phrase in that sense, and we have never similarly limited the “motion in bar” provision to its common-law scope. The alleged trouble with the “motion in arrest” is not any problem of jeopardy, but the fact that Judge Wyzanski relied on facts outside the face of the “record.” Conversely, the trouble with the “motion in bar” provision is not the use of outside facts, but solely the fear that Sisson was “put in jeopardy.” If this were a motion in arrest, there would be no “jeopardy” problem; and if this were a motion in bar, resort to outside facts would pose no problem. The apparent inconsistency and the refusal to hear the case appear to be due to a dogged determination to fit Judge Wyzanski’s action into one “common-law pigeonhole,” United States v. Mersky, 361 U. S. 431, 442 (Brennan, J., concurring), or the other *347while paying scant attention to the reason for trying to make the fit in the first place, with the result that Judge Wyzanski’s action is to be given the no less distorting label of “acquittal.”

The question in this case should simply be whether or not a judge who upholds a claim of constitutional privilege, thereby declaring the statute unconstitutional as applied, has entered a judgment that Congress intended this Court to be able to review. Surely in a statute as unclear and ambiguous as the majority says this unhappy Act is, the “words” of the statute are only the first place to start the task of interpretation. The primary guide to interpretation should be the statute’s purpose, as indicated by the evil that prompted it, and by the legislative history.

The Act was passed to remedy the situation that gave a single district judge the power to defeat any criminal prosecution instituted by the Government, and to annul as unconstitutional, attempts by Congress to reach a defendant’s specified conduct through the use of the criminal machinery. Over and over, this theme is repeated in the debates on the bill, dominating every other topic of discussion except the concern for safeguarding the defendant’s privilege against double jeopardy. As The Chief Justice’s opinion details, it is difficult to imagine a case more closely fitting the type of case in which Congress intended to allow an appeal than the instant one.

The majority suggests that we must remember that the Act was “a compromise,” and that Congress was very concerned about not unduly encroaching on the rights of the defendant. But the “compromise” between the House and the Senate was only over the areas in which to allow appeal — there was complete accord that constitutional cases of this sort constituted one of those areas; they were indeed the Act’s raison d’etre. Simi*348larly while Congress was concerned to protect the defendant’s rights, it had no doubt that those rights were not invaded where a defendant had been found guilty, and the Government appealed the judge’s decision that for legal reasons the verdict could not stand. The majority, in short, pays lip service to the policies of the Act without ever applying those policies to the question presented in the case before it. Judge Wyzanski, anxious to do his duty as he saw it, and yet aware that ultimate resolution of the constitutional issue properly belongs in this Court, had two means of passing on the issue while still protecting Sisson’s rights: he could have granted Sisson’s motion after a pretrial hearing, see United States v. Covington, 395 U. S. 57, 60; Fed. Rules Crim. Proc. 12 (b)(1), 12 (b)(4), or he could, as here, grant the motion only after the jury’s verdict of guilty forced him to reach the constitutional question. In either case, none of the interests reflected in the jeopardy provisions of the Constitution — protecting defendants from repeated and harassing trials for the same offense — is in any way endangered. In fact, Sisson’s interests if anything are less in jeopardy in the second case than the first where the Government’s appeal would force a long delay in beginning the trial itself.

The conclusion that Congress intended judgments of this kind to be reviewed seems to me so clear, that I suspect the majority’s neglect of this aspect of the statute amounts to a tacit admission that policy and purpose point overwhelmingly toward finding jurisdiction. If that- is the case, then to hang Congress on the technical meaning of the obscure legal terms it happened to use is not only inappropriate, but is strangely out of line with decisions that leap over the plain meaning of words in other contexts to reach conclusions claimed to be consistent with an Act’s broader purposes. See Welsh v. United States, 398 U. S. 333 (1970); Boys *349Markets, Inc. v. Retail Clerks Union, 398 U. S. 235 (1970); Toussie v. United States, 397 U. S. 112 (1970); United States v. Seeger, 380 U. S. 163 (1965). Compared to some of these examples of “statutory construction,” it is child’s play to conclude that Congress did not really mean to limit “motion in arrest” to its old common-law meaning, or that at least if it did, it thought decisions such as Judge Wyzanski’s would have been appealable under some other provision, such as the “motion in bar” as long as there was no danger of encroaching on the defendant’s jeopardy interests.

Admittedly, the issues raised by Sisson are difficult and far-reaching ones, but they should be faced and decided. It is, to be sure, much more comfortable to be able to control the decision whether or not to hear a difficult issue by the use of our discretion to grant certiorari. But that is no excuse for ignoring Congress’ clear intent that the Court was to have no choice in deciding whether to hear the issue in a case such as this. The fear expressed in the prevailing opinion that if we accept jurisdiction we shall be “cast adrift” to flounder helplessly, see ante, at 299, has a flavor of nothing so much as the long-discarded philosophy that inspired the old forms of action and that led to the solemn admonition in 1725 that “[w]e must keep up the boundaries of actions, otherwise we shall introduce the utmost confusion.” Reynolds v. Clarke, 93 Eng. Rep. 747, 748 (K. B. 1725). I cannot agree. I would find jurisdiction.