However, we believe that reversible error was committed, to defendant’s substantial prejudice, when the District Attorney was permitted to read into the record a stenographic transcript of defendant’s confession to an Assistant District Attorney of a stabbing of which he had been convicted more than a decade and a half earlier, and which closely resembled the case in which he was then on trial. Defendant admitted his plea of guilty to the earlier crime. That should have been sufficient for purposes of attack on credibility—the only legitimate purpose of an inquiry into a prior conviction
(People v Sandoval, 34 NY2d 371 ). However, when defendant endeavored to explain his plea by stating that his choice was between so pleading while innocent and running the risk of a 30-year term if convicted, this collateral matter was then blown up by the introduction of the damning statement, pursued further and further in complete detail. The close similarity between the facts of this and his earlier case virtually guaranteed a prejudicial effect. This not alone; it was compounded by the court’s interjection of disbelief that an innocent defendant pleaded guilty. While the use of the statement is attempted to be justified by the defendant’s assertion of innocence, the matter is no less collateral. The use of the statement was improper and prejudicial beyond argument. (See
People v McCormick, 303 NY 403 .) A new trial is called for. Concur—Stevens, P. J., Markewich and Lynch, JJ.; Capozzoli and Nunez, JJ., dissent in a memorandum by Nunez, J., as follows: Introduction into evidence of the details of defendant’s confession to an earlier knife homicide did not deny defendant a fair trial. Defendant admitted the stabbing with which he is presently charged. At trial the sole issue was whether defendant’s acts which resulted in the decedent’s death were justified as performed in self-defense. In
People v Crimmins (
36 NY2d 230 ), the Court of Appeals provided guidelines to determine the effect on a trial of nonconstitutional errors. The threshhold question to be considered is whether guilt would be proven if the error were excised. In the case at bar proof of guilt is overwhelming, even absent the alleged error. The victim was stabbed 12 times. Defendant had the opportunity to escape the altercation prior to delivering the fatal blows. Even if the victim had a knife, as alleged by defense witnesses, the victim had surrendered it prior to the fatal blows. Where conflicting testimony exists, the jury, which has the opportunity to evaluate the witnesses, is the proper body to determine who is telling the truth. However, the inquiry of the appellate court does not stop with the determination of guilt. An evaluation must now be made of the potential of the error for prejudice to the defendant. The test adopted in
People v Crimmins (supra, p 242 ), is: "if the appellate court concludes that there is a significant probability, rather than only a rational possibility, in the particular case that the jury would have acquitted the defendant had it not been for the error or errors which occurred.” In the case at bar, there does not exist a significant probability that without introduction of the confession defendant would have been acquitted. A defendant, like any witness, may be questioned upon cross-examination as to any act or thing which may discredit him,
People v Webster ( 139 NY 73 , 84). It is not improper for a prosecutor, acting in good faith, to continue his cross-examination about a specific crime after defendant has denied committing it,
People v Sorge (
301 NY 198 ). An exception to the general rule that collateral evidence cannot be admitted to contradict defendant’s denials, allows introduction of evidence to prove any previous conviction denied or equivocated to by the defendant (CPL 60.40, subd 1;
People v Sorge, supra). However, in
People v Sandoval ( 34 NY2d 371 ), decided after the trial herein, the Court of Appeals approved of pretrial