It may, in general, be considered the rule that when proceedings are commenced against a person for an alleged offense, upon a complaint before a justice of the peace, in a matter where he has final jurisdiction, arid the accused is arraigned, tried and discharged as not guilty, and judgment has been entered thereon, he can not be again put on trial, under another similar complaint, for the same offense. Stevens v. Fassett, 27 Me. 266; N. H. Bill of Rights, Art. 16. And a plea of autrefois acquit, made by a defendant in due form, indicted for a crime or misdemeanor, alleging that he has formerly *476been tried and acquitted of the foi'mer offense, would be good. But, to be a bai’, the acquittal must have been by trial. There must be an .acquittal of the offense chax’ged, in law and in fact, by a verdict of a jury, on a valid indictment, or by some competent tribunal that has jurisdiction of the offense. Hawk., B. 2, eh. 25, sec. 1; 4 Black. Com. 385 ; 1 Ch. Or. Law 452.

Bid the police magistrate of Manchester, under the first complaint against the respondent, so txy him as legally to justify or sustain this plea? The case shows the respondent to have been chai’ged with an assault and battexy, and that he was arx*aigned and pleaded to the complaint not guilty, and that his case was continued; and that at the trial upon the continuance these px’oceedings were discontinued by the entxy of a nolle prosequi. So far, thexx, the merits of the case do not appear to have been inquired into, and the defendant was not put ixx pexil. A plea of previous conviction can not be sustained, unless it appear that, finder the first indictment or complaint, the real merits may have been inquired into, and the x’espondent was actually in jeopardy. Commonwealth v. Curtis, Thatcher’s Cr. Cases 202. A nolle prosequi, entered on an indictment by the prosecuting officer, is no bar to axxother indictment for the same offense. Commonwealth v. Wheeler, 2 Mass. 172; State v. Tindall, 5 Harr. 488. Unless it appear affirmatively that a former trial was decided on the mexfits, the plea of a former acquittal is bad. Hassell v. Nutt, 14 Texas (19 U. S. Dig.) 85. Hence, on this ground, the defendant’s plea is not sustained.

But it appears by the case that the respondent was the second time ai’raigned before the police magistrate, upon a complaint for an assault upon the same person, with the attempt to commit a rape. Upon this, the record recites, that the respondent was heard, and that there was no just ground for holding him to answer to this complaint, and he was discharged. The answer to this part of the case is, *477that the magistrate had no final jurisdiction of this complaint. He had no power to try the offense alleged under the second complaint. It was by our statute made a state prison offense. He could only examine and ascertain if there was a sufficient cause for putting the defendant upon trial before a court competent to make a final disposition of the case. The court say, in Marston v. Jenness, 11 N. H. 162, the essence of the plea autrefois acquit is, that the defendant was legitimo modo acquietatus, by a court of competent jurisdiction to try him. The opinion of a court of inquiry, which has no final jurisdiction in the case, is conclusive upon no one. If it were, no party could be indicted against whom a former grand jury had refused to find a bill, or whom a magistrate had once refused to bind over. This authority, united with a long, uniform practice, appears to be decisive upon this point. State v. Place, not reported; Comp. Laws, ch. 227, sec. 3. State v. Webster, 39 N. H. 98; Commonwealth v. Tuck, 20 Pick. 356. A plea of a former acquittal, by a justice of the peace, of an offense of which he has no jurisdiction, is no bar to an indictment for the same offense. State v. Payne, 4 Miss. 376; State v. Odell, 4 Blackf. 156; Sanborn v. Fellows, 22 N. H. 473.

The fact, therefore, that the respondent was tried on the second complaint, and acquitted for the reasons given, can not avail him as a plea in this case. From the case it also appears that the magistrate considered the offense committed by the respondent as au assault and battery of an aggravated character, and, therefore, ordered him to recognize to appear at the higher court. If the evidence justified the magistrate in coming to this conclusion, it was within his discretion so to find. This furnishes another and additional reason why the defendant’s plea can not be allowed. To an indictment for an assault and battery of an aggravated character, a plea of a former conviction before a justice of the peace is no defense, the *478justice having no final jurisdiction. State v. Flournoy, 16 Texas 30 (19 U. S. Dig. 85).

There does not appear to us to be any sufficient grounds upon which this plea can stand, and the exception to the ruling of the judge who tried the case must be overruled, and the respondent answer further.