Massachusetts Guide to Evidence 2025 Edition MA R EVID § 509

(1)Stage One. The judge must first determine whether the Commonwealth has properly asserted the privilege by showing that disclosure would endanger the informant or otherwise impede law enforcement efforts. If such a finding is made, the judge must determine whether the defendant has offered some evidence that the privilege should be set aside on grounds that it interferes with the defense.

(2)Stage Two. If the judge finds that the privilege has been properly asserted and that, if recognized, it would interfere with the defense, the judge must undertake a balancing test in order to determine whether disclosure of the informant's identity and information is sufficiently relevant and helpful to the defense. The judge must consider the crime charged, the possible defenses, the possible significance of the privileged testimony, and other relevant factors in balancing the public interest in the free flow of information and the individual's interest in preparing a defense. There is no privilege under this subsection when the identity of the informer has been disclosed by the government or by the informer, or the court determines that it is otherwise known.

(1) the prosecuting officer agrees to a disclosure after balancing the danger posed to the protected witness, the detriment it may cause to the program, and the benefit it may afford to the public or the person seeking discovery, or

(2) disclosure is at the request of a local, State, or Federal law enforcement officer or is in compliance with a court order in circumstances in which the protected witness is under criminal investigation for, arrested for, or charged with a felony.