Smith, J., dissents in a memorandum as follows: The motion court erred when it (1) refused to permit the defense attorney to speak with or call to testify at the suppression hearing the police officer whose observation allegedly established probable cause, (2) refused to require the People to call that officer, and (3) incorporated part of the grand jury testimony of the officer who allegedly witnessed a sale into its findings.
The sole witness at the hearing on the motion to suppress narcotics was Police Officer James Shea. He testified as follows: Around 7:00 p.m. on October 12,1989, he and his partner were on radio motor patrol on 47th Street between Ninth and Tenth Avenues in Manhattan. While Officer Shea testified on direct examination that he had received a message from Officer Carney of a narcotics transaction, Officer Shea further testified on cross examination that Officer Carney told him only that there had been "a hand to hand” by two males. One man, the defendant, who was the alleged seller, was described. The officers proceeded to Tenth Avenue and went northbound where they saw the individual described walking towards them. As the officers exited their car, Officer Carney made another broadcast that this was the man. Officer Shea approached the defendant and told him to stop. The defendant quickened his pace and entered a delicatessen. There the defendant reached into his right jacket pocket, took out a brown paper bag and threw it over the counter. Officer Shea recovered the bag, which contained one hundred vials of crack, while his partner, Officer Fitzgerald, prevented the *299defendant from escaping. The defendant was arrested and identified by Officer Carney.
After the testimony of Officer Shea, defendant sought to speak with Officer Carney and to put him on the stand. The prosecutor objected and the court refused to permit the defense attorney either to speak with Officer Carney or to call him. The defense sought to establish that Officer Carney had not seen “a narcotics exchange” or what was exchanged between defendant and the other man who was not apprehended.
At a suppression hearing, the People have the burden of going forward to show the legality of police conduct (People v Chipp, 75 NY2d 327, 335 [1990], cert denied 498 US 833, [1990]). The police may establish probable cause in a "buy and bust” operation by the testimony of the arresting officer alone without calling the observing officer (People v Petralia, 62 NY2d 47 [1984], cert denied 469 US 852 [1984]). Where an issue of probable cause is raised by the arresting officer's testimony, however, the observing officer should be called (People v Petralia, 62 NY2d, supra, at 53). Here, the arresting officer did not establish probable cause by his statement that Officer Carney referred only to a "hand to hand.” Moreover, Officer Carney’s grand jury testimony, improperly used as evidence in the suppression hearing, did not establish an exchange of money and narcotics. Officer Carney testified in the grand jury to seeing "a small package” exchanged for money. In this case the People simply failed to present sufficient proof to establish the legality of police conduct.