The defendant appeals from his conviction of unlawfully distributing a controlled substance. As the facts of this case are indistinguishable in principle from those of Commonwealth v. Ennis, 1 Mass. App. Ct. 499 (1973), it was error for the judge to deny the defendant the name of the informant who had accompanied the undercover police officer to the meeting with the drug seller and who was clearly in a position to make an in-court identification of the seller.

Judgment reversed.

Verdict set aside.