By his plea of guilty when first arraigned in the municipal court the defendant admitted the substantive allegations of the complaint, and while his appeal to the Superior Court after conviction vacated the judgment, it did not change the issue, which had been joined, or entitled him to a jury trial, and on the record nothing remained to be done except to impose sentence. Commonwealth v. Mahoney, 115 Mass. 151. Commonwealth v. Ingersoll, 145 Mass. 381, 382.
The appellate court, however, upon the defendant’s application, which seems to have been made seasonably, could permit him to withdraw the plea below, and plead anew, if satisfied that his admission of guilt was not voluntary and intentional, but resulted from inadvertence. Commonwealth v. Winton, 108 Mass. 485. It was incumbent on the defendant, if required, to offer evidence to support the request; but at the hearing, and in response to a statement by the presiding judge that the court would hear testimony if he had any to offer, the defendant stated that he would rely entirely upon the affidavit annexed to the motion. The memorandum and order denying the motion are equivocal. It is not certain whether the denial rested on the ground that the affidavit could not be received as evidence, or whether its recitals were rejected because the judge did not believe them to be true. But while the affidavit is sufficient in form and substance, yet, if treated as testimony, the credibility of the affiant and the truth or falsity of the statements were questions of fact upon which the decision of the judge is final. American Malting Co. v. Souther Brewing Co. 194 Mass. 89. Deane v. American Glue Co. 200 Mass. 459, 464.
The objection to evidence resting only on ex parte affidavits, when application is made to the court for permission to withdraw an incriminating plea, is that the means of knowledge, or the truth of. the intermediate facts on which the general conclusions are founded, cannot be ascertained. The affiant, especially if he is an interested party, can mould the evidentiary statements in conformity with the exigencies of the case. At the hearing the defendant’s guilt or innocence was not in issue, and he could have testified as a witness in his own behalf without being compelled *211to give evidence which could be used against him at the trial of the complaint. R. L. c. 175, § 20. By his resorting to a statement in writing, even if made under oath, the court was not required to receive in evidence the affidavit, and whichever way was taken no error of law appears. Walsh v. Rogers, 13 How. 283. Baldwin v. Flagg, 14 Vroom, 495. Wigmore on Ev. §§ 1384, 1708. See also R. L. c. 175, § 45.
Order affirmed,.