Appeal by the defendant from a judgment of the Supreme Court, Kings County (Slavin, J.), rendered March 17, 1986, convicting him of criminal sale of a controlled substance in the third degree, upon a jury verdict, and imposing sentence.
Ordered that the judgment is reversed, on the law, and a new trial is ordered; no questions of fact have been raised or considered.
Under the circumstances of this case, the trial court erred by refusing the defense counsel’s timely request for a missing witness charge with respect to the partner of the undercover officer who allegedly purchased cocaine from the defendant and a coperpetrator. The transaction took place on a sunny August afternoon. The undercover police officer and his partner parked their vehicle on the north side of Lott Avenue in Brooklyn facing west and just east of 53 Lott Avenue. The undercover police officer stepped out onto the sidewalk while the driver remained in the vehicle. A person identified as the defendant approached on a bicycle and asked the undercover officer what he wanted. The undercover officer replied, "twenty rock”, which meant $20 worth of cocaine. This conversation took place "[i]mmediately to the [passenger’s] side” of the vehicle. The undercover officer then followed the defendant west on Lott Avenue approximately 5 to 10 feet where the coperpetrator gave the defendant two tinfoil packets. The defendant opened one of the packets, displaying a white powder, and then gave it to the undercover officer in exchange for $20 in marked bills. This transaction took place on the sidewalk despite the undercover officer’s request that they retire to a nearby alley. The undercover officer then returned *507to his vehicle. He testified that from the vehicle he could see the defendant and the coperpetrator still standing on the sidewalk. The driver, who remained in the vehicle throughout the transaction, did not testify, nor was there any information provided as to his whereabouts or availability at the time of the trial.
The defendant was arrested while riding his bicycle a short distance from the scene of the transaction a few minutes later. He had no drugs or marked money on him at the time. The coperpetrator was arrested at the scene. He had cocaine and $15 of the marked bills. The defendant testified that he was in the area because he had gone to 41 Lott Avenue to speak to the superintendent about employment. He denied any knowledge about a drug transaction.
On this evidence, we hold that the defendant established prima facie that the undercover officer who was not called as a witness was knowledgeable about a material issue, i.e., the identity of the drug seller, which evidence was already in the case (see, People v Gonzalez, 68 NY2d 424, 427). It was established that the officer was in a position to observe the entire transaction. In addition, that officer would naturally be interested in the transaction and in the safety of his fellow officer. Thus, he would, presumably, have been motivated to pay attention to the events transpiring on the sidewalk. The defendant further established that the uncalled witness was in the control of the prosecution in that the witness would naturally be expected to provide testimony favorable to the prosecution (see, People v Gonzalez, supra; People v Paduano, 125 AD2d 715, 718, lv denied 70 NY2d 652). Finally, the issue of identity was seriously contested, and there is no indication that the driver’s testimony would have been merely cumulative (see, People v Gonzalez, supra, at 430; see also, People v Wright, 41 NY2d 172, 176; People v Brown, 34 NY2d 658, 660). Thus, the defendant met the threshold requirements, and the burden shifted to the prosecution to show that the witness was unavailable. Because no information was offered in this regard, the defendant’s request for a missing witness charge should have been granted. Although the evidence was legally sufficient, it was not so strong as to permit this error to be disregarded. Accordingly, a new trial is necessary.
We further note that at the new trial, the court should marshal the evidence in a balanced manner. A trial court is required to marshal the evidence only "to the extent necessary to explain the application of the law to the facts of the case” (People v Saunders, 64 NY2d 665, 667; CPL 300.10 [2]), *508and need not "explain all the contentions of the parties or outline all the inconsistencies in the evidence” (People v Saunders, supra, at 667). However, to the extent that the court does refer to the evidence, it must be done in an evenhanded manner (see, People v Chambers, 73 AD2d 976). In this case, the People’s evidence was described in detail with no mention of any inconsistencies, while the defendant’s testimony was stated briefly with mention of the sole inconsistency adduced during cross-examination (see, People v Williamson, 40 NY2d 1073, 1074). Although standing alone this error was not so egregious as to warrant reversal, at the new trial it should be avoided. Bracken, J. P., Brown and Spatt, JJ., concur.