Mass. Dist./Mun. Cts. R. Crim. P. 6

(a) In the District Court

(1) Discovery Motions

Discovery motions shall be filed in accordance with Rule 4(b) and shall be heard and decided prior to the defendant's initial decision on waiver of jury trial, provided, however, that motions for discovery may be filed within twenty-one days after the defendant's initial decision on waiver of jury trial, or later, for good cause shown. Discovery motions filed within said twenty-one day period or later shall be entertained only upon a preliminary showing (1) that the items or information sought could not reasonably have been sought and obtained prior to the initial decision on waiver of jury trial or (2) of other grounds that the court determines reasonably justify the delay in having filed the discovery motion after completion of the pretrial hearing.

(2) Non-Discovery Pretrial Motions

All pretrial motions other than those involving discovery may be filed before or after the defendant's initial decision on waiver of the right to jury trial.

Such motions filed before the defendant's initial decision on the waiver of jury trial shall be transmitted to the appropriate trial session and scheduled to be heard there on the trial date, provided, however, that the judge before whom any such motion is filed may, as a matter of his or her discretion, hear and decide said motion (1) prior to the trial date, or, (2) where the trial will be conducted in a different court, prior to transmission of the case to such other court.

Such motions filed after defendant's initial decision on waiver of jury trial shall be filed in the court wherein the trial is scheduled to be heard no later than twenty-one days after defendant's decision on waiver of jury trial, or later, for good cause shown. Notwithstanding the foregoing, the presiding justice of the court in which the pretrial hearing is conducted, if different from the court in which the trial will be conducted, may require that such motions be filed and heard in the former court. In such cases, transmission of the case file to the other court for trial should be deferred until after the motion is heard and decided.

Rulings on pretrial motions rendered prior to the transmission of a case to a trial session shall be final, as provided in G.L. c. 278, § 18.

(b) In the Boston Municipal Court

(1) Discovery Motions

Discovery motions timely filed must be heard and decided prior to the scheduling of the trial session assignment date. Discovery motions filed after the scheduling of a trial session assignment date shall be allowed only:

(A) if the discovery being sought could not reasonably have been sought or obtained prior to the scheduling of the trial session assignment date; or

(B) if other good cause can be shown.

(2) Non-Discovery Pretrial Motions

Pretrial motions other than those involving discovery may be filed at any time but no later than 21 days after the date of the filing of the Pretrial Conference Report.

Rulings on pretrial motions rendered prior to the transmission of a case to a trial assignment session shall be final, as provided in G.L. c. 278, § 18.