Mass. Gen. Laws ch. 278 § 28E
An appeal may be taken by and on behalf of the commonwealth by the attorney general or a district attorney from the district court to the appeals court in all criminal cases and in all delinquency cases from a decision, order or judgment of the court (1) allowing a motion to dismiss an indictment or complaint, (2) allowing a motion to suppress evidence, or (3) denying a motion to transfer pursuant to section sixty-one of chapter one hundred and nineteen.
An appeal may be taken by and on behalf of the commonwealth by the attorney general or a district attorney from the superior court to the supreme judicial court in all criminal cases from a decision, order or judgment of the court (1) allowing a motion to dismiss an indictment or complaint, or (2) allowing a motion for appropriate relief under the Massachusetts Rules of Criminal Procedure.
An application for an appeal from a decision, order or judgment of the superior court determining a motion to suppress evidence prior to trial may be filed in the supreme judicial court by a defendant or by and on behalf of the commonwealth by the attorney general or a district attorney. If such application is denied, or if such application is granted but the interlocutory appeal is heard by a single justice, the determination of the motion to suppress evidence shall be open to review by the full court after trial in the same manner and to the same extent as determinations of such motions not appealed under the interlocutory procedure herein authorized.
Rules of practice and procedure with respect to appeals authorized by this section shall be the same as those applicable to criminal appeals under the Massachusetts Rules of Appellate Procedure.
Mass. Gen. Laws ch. 278, § 28E