Judgment unanimously reversed, on the law, and a new trial granted. Memorandum: Defendant appeals from his conviction of assault in the second degree committed upon Tonawanda Police Officer James Carney (Penal Law § 120.05 [3]), contending that the trial court erred (1) in allowing the prosecutor to attempt to impeach defendant’s character witnesses by permitting questions concerning a prior conviction and (2) by restricting cross-examination of Officer Carney regarding allegations of fraud in the securing of a loan, which were the subject of a then pending civil trial.

Character witnesses may be cross-examined "as to the existence of rumors or reports of particular acts allegedly committed by the defendant which are inconsistent with the reputation they have attributed to him” (People v Kuss, 32 NY2d 436, 443) but the scope of cross-examination is "limited to the trait the witnesses testified to on direct examination.” (People v Lediard, 80 AD2d 237, 242; see, Michelson v United States, 335 US 469, 483-484; see also, People v Alamo, 23 NY2d 630, 634.) Defendant’s character witnesses testified solely with respect to his reputation for peaceableness and his prior conviction had no logical connection to this character trait; consequently the cross-examination was improper.

A witness may be cross-examined "as to any criminal, vicious or disgraceful acts in his life that have a bearing on his credibility” (People v Ayrhart, 101 AD2d 703, 704), and denial of the right to full cross-examination of prosecution witnesses may deprive defendant of "his constitutional right to cross-examine his accusers” (People v Allen, 67 AD2d 558, 560, affd 50 NY2d 898). Not "every error which improperly curtails a defendant’s right to cross-examine a prosecution witness * * * is per se reversible error” (People v Allen, 50 NY2d 898, 899, supra); nevertheless, "such a limitation in a case where the 'issue of the credibility of * * * the prosecution witnesses [is] crucial’ constitutes reversible error”. (People v Ayrhart, 101 AD2d 703, 704, supra.) Here, Officer Carney’s credibility was crucial to the prosecution of defendant for[*800] assault in the second degree which was built on a chain of circumstance founded on the conclusion that Officer Carney lawfully entered the City of Buffalo to effect a traffic stop for an infraction committed in Tonawanda. The propriety of defendant’s arrest centers around the legality of Officer Carney’s presence in Buffalo and his credibility was a crucial issue.

Although we would be reluctant to reverse this conviction based on either error standing alone, the cumulative effect of these errors was prejudicial and deprived defendant of a fair trial. The effect of the errors was to subject defendant to an unfair attack on his character while insulating a prosecution witness from full cross-examination. The overall impact of these errors requires a reversal and the grant of a new trial. We have examined other issues raised by defendant and find them to be without merit. (Appeal from judgment of Supreme Court, Erie County, Marshall, J. — assault, second degree.) Present — Doerr, J. P., Boomer, O’Donnell, Pine and Schnepp, JJ.