— Judgment unanimously affirmed. Memorandum: The court did not err in precluding cross-examination of the police witness concerning acts committed by the "Hit Squad,” of which the witness was a member. The extent of cross-examination of a witness upon matters immaterial to the issue is within the discretion of the trial court, and the exercise of its discretion may not be reviewed on appeal in the absence of plain abuse and injustice (People v Sorge, 301 NY 198, 201-202; La Beau v People, 34 NY 222, 230). Further, the court did not err in refusing to permit defendant access to confidential personnel records of the witness, inasmuch as defendant did not provide facts sufficient to establish that it was reasonably likely that the file would contain information bearing upon the credibility of the witness (see, People v Gissendanner, 48 NY2d 543, 550). (Appeal from Judgment of Monroe County Court, Marks, J. — Criminal Possession Controlled Substance, 3rd Degree.) Present — Den-man, P. J., Boomer, Lawton, Fallon and Doerr, JJ.