delivered the opinion of the Court.

In 1913, at the age of 10 years, petitioner was brought to the United States as an immigrant from Poland. In June 1938 the United States District Court for the Eastern District of Michigan entered its order admitting him to citizenship. More than 14 years later, in December 1952, the United States brought this suit under § 338 (a) of the Nationality Act of 19401 to set aside the naturalization decree, alleging that Nowak had obtained his citizenship both fraudulently and illegally. The Government filed with its complaint an “affidavit showing good cause,” as required by § 338 (a). After a trial the District Court granted the relief requested by the United States on the grounds that Nowak (1) fraudulently obtained citizenship by making a false answer to a question in his Preliminary Form for Petition for Naturalization, filed in July 1937; and (2) illegally obtained citizenship, in that for a period of five years preceding his *662naturalization he had not been “attached to the principles of the Constitution of the United States . . . ,” as required by § 4 of the Nationality Act of 1906,2 under which he was naturalized. 133 F. Supp. 191. The Court of Appeals affirmed, 238 F. 2d 282, and we granted cer-tiorari. 353 U. S. 922. For reasons given hereafter we decide that the judgment below must be reversed.

1. “Good Cause” Affidavit. — Petitioner, relying on United States v. Zueca, 351 U. S. 91, contends that the District Court lacked jurisdiction over this proceeding because the Government’s affidavit of “good cause” was defective, in that it was not made by one having personal knowledge of the matters contained therein. This contention must be rejected. The affiant was an attorney of the Immigration and Naturalization Service who swore that the allegations made in his affidavit were based upon facts disclosed by official records of the Naturalization Service to which he had had access. In substance the affidavit set forth the same matters upon which the District Court’s later decree of denaturalization was based, and showed with adequate particularity the grounds on which the Government’s suit rested. Sworn to as it was by a responsible official of the Naturalization Service, we consider that the affidavit satisfied the purpose of § 338 (a) to protect those proceeded against from ill-considered action. See United States v. Zueca, supra, at 99-100.

*6632. Fraudulent Procurement. — The finding of fraud here was based on Nowak’s answer to Question 28 in the above-mentioned preliminary naturalization form, which read:

“28. Are you a believer in anarchy? . . . Do you belong to or are you associated with any organization which teaches or advocates anarchy or the overthrow of existing government in this country? . . .”

Nowak placed “No” after each part of the question. The courts below ruled that he should have answered “Yes” to the second part because in 1937, when the form was executed, (1) Nowak was a member of the Communist Party; (2) the Party taught “the overthrow of existing government”; and (3) Nowak was aware of this Party teaching. Accordingly the charge of fraudulent procurement was sustained.

Where citizenship is at stake the Government carries the heavy burden of proving its case by “ ‘clear, unequivocal, and convincing’ evidence which does not leave ‘the issue in doubt’ . . . .” Schneiderman v. United States, 320 U. S. 118, 158. “Especially is this so when the attack is made long after the time when the certificate of citizenship was granted and the citizen has meanwhile met his obligations and has committed no act of lawlessness.” Id., at 122-123. See also Baumgartner v. United States, 322 U. S. 665, 675. And in a case such as this it becomes our duty to scrutinize the record with the utmost care. Cf. Dennis v. United States, 341 U. S. 494, 516; Yates v. United States, 354 U. S. 298, 328.

Applying the strict standard required of the Government by Schneiderman, we rule that the charge of fraud was not proved: first, Question 28 on its face was not sufficiently clear to warrant the firm conclusion that when Nowak answered it in 1937 he should have known that it *664called for disclosure of membership in nonanarchistic organizations advocating violent overthrow of government and, more particularly, membership in the Communist Party; second, even if the question should have been taken as calling for disclosure of membership in such organizations, as the Government claims, the evidence, as we decide below in connection with the charge of illegal procurement, was insufficient to establish that Nowak knew that the Communist Party engaged in such illegal advocacy. We deal with the first of these grounds here.

No claim is made that Nowak’s answer to the first part of Question 28 was untruthful. The issue is whether, as Nowak claims, the second part of the question could reasonably have been read by him as inquiring solely about membership in an anarchistic organization, or whether, as the Government contends, it unambiguously called for disclosure of membership in an organization which advocates either anarchy or overthrow of existing government.

We think that Nowak could reasonably have interpreted Question 28 as a two-pronged inquiry relating simply to anarchy. Its first part refers solely to anarchy. Its second part, which is in direct series with the first, begins with “anarchy,” and then refers to “overthrow.” It is true that the two terms are used in the disjunctive, but, having regard to the maxim ejusdem generis, we do not think that the Government’s burden can be satisfied simply by parsing the second sentence of the question according to strict rules of syntax. For the two references to “anarchy” make it not implausible to read the question in its totality as inquiring solely about anarchy. Especially is this so when it is borne in mind that Nowak answered the question in 1937, during a period when communism was much less in the public consciousness than has been the case in more recent years, and when, *665accordingly, there was less reason for individuals to believe that government questionnaires were seeking information relating to Communist Party membership.3 The fact that the Nationality Act of 1906, under which this preliminary naturalization form was issued, prohibited anarchists, but not Communists, from becoming American citizens, see 34 Stat. 596, 597, 598, accentuates the highly doubtful meaning of the question. We hold the second part of Question 28 too ambiguous to sustain the fraudulent procurement charge based on petitioner’s answer to it.

3. Illegal Procurement. — As in the Schneiderman case, the Government here undertook to prove that Nowak, during the five years preceding his naturalization, was not “attached” to the principles of the Constitution by showing that he had been a member of the Communist Party with knowledge that the Party advocated the overthrow of the Government by force and violence. We believe that the Government has adequately proved that Nowak was a member of the Party during the pertinent five-year period. But even assuming that the evidence of the illegal advocacy of the Party was sufficient, see Yates v. United States, supra, at 319-322, and that, despite the doubts expressed in Schneiderman v. United States, supra, at 136, 154, lack of “attachment” could be *666proved by this method, we nevertheless hold that the Government cannot prevail on this record. For we are of the opinion that it has not been established that Nowak knew of the Party’s illegal advocacy.

The fact that Nowak was an active member and functionary in the Party does not of itself suffice to establish this vital link in the Government’s chain of proof. See generally Schneiderman v. United States, supra; cf. Yates v. United States, supra, at 329-330. Nor is the Government’s burden satisfied on the crucial issue of Nowak’s awareness of the illegal aspects of the Party’s program by the evidence of his attendance at “closed” Party meetings, or by the disputed evidence as to his alleged concealment of Party membership. Virtually the only testimony at the trial bearing directly on Nowak’s state of mind related to three statements attributed to him by former members of the Communist Party. One testified that at the meeting at which Nowak joined the Party in 1935 he stated that it would be necessary to “destroy” capitalism in order to set up a workers’ government. A second testified that about 1937 Nowak stated at a Party meeting that the Party could not rely entirely on the ballot to gain its objectives, “but that it would eventually resolve to bullets.” And a third testified that in the summer of 1937, while lecturing at a Party school, Nowak said that if the Party could not gain control of labor unions through elections, “then it may be necessary to use violence to get it,” and that “the goal of all this activity was to extend the Soviet system around the face of the earth.”

For a number of reasons we cannot regard these fragmentary episodes as providing rehable support for the Government’s case. On their face each of the statements attributed to Nowak was equivocal. Read in context, they can be taken as merely the expression of opinions or predictions about future events, rather than as advocacy *667of violent action for the overthrow of government. See Schneiderman v. United States, supra, at 157-158; cf. Yates v. United States, supra, at 319-322. The record reveals that in two of these instances Nowak was not even addressing himself to political action, but rather to Party activity designed to strengthen the American labor movement, in which he was a union organizer. At no point does the record show that Nowak himself ever advocated action for violent overthrow, or that he understood that the Party advocated action to that end. In addition, the record leaves us with the distinct impression that the testimony as to these episodes was itself quite uncertain, given as it was from 17 to 19 years after the event. Indeed, some of the testimony was elicited only after persistent prodding by counsel for the Government.4

*668Under the strict standard of proof by which this case must be judged, the record shows at best from the Government’s standpoint that Nowak was an active member and functionary of the Communist Party. But this proof does not suffice to make out the Government’s case, for Congress in the Nationality Act of 1940 did not make membership or holding office in the Communist Party a ground for loss of citizenship. We conclude that the Government has failed to prove its charges of fraud and lack of “attachment” against this petitioner by the “clear, unequivocal, and convincing” evidence which is required in denaturalization cases. We therefore need not consider any of the other contentions pressed by petitioner.

The judgment of the Court of Appeals is reversed and the case is remanded to the District Court for further proceedings in conformity with this opinion.

Reversed.

dissenting.*

We join the Court in concluding that the “good cause” affidavits were sufficient. However, undér the circumstances of these cases we believe that each petitioner fully understood the thrust of Question 28 as to association with or membership in any organization which teaches or advocates the overthrow of the Government. Further, we believe that the facts amply support the conclusion of both the trial court and the Court of Appeals that neither petitioner “behaved as a person ... attached to the principles of the Constitution of the United States . . . .” We cannot join in overturning these findings of two courts, and therefore would affirm the judgments.