MPG: Gateway

Welcome to MASSACHUSETTS CRIMINAL LAW: A PROSECUTOR'S GUIDE Online.

On this site, you will find the full text of the 42nd edition of the Prosecutor's Guide. The Guide presents a timely and comprehensive analysis of Massachusetts criminal law and its practice in the courts of the Commonwealth. It is fully updated each fall and during the year as new developments in the law warrant. Please consult our What's New page for the most recent changes. In addition, this online text is linked to a database of Massachusetts court decisions maintained by the Trial Court Law Libraries at masscases.com.

The text also cites and discusses significant criminal law cases decided by the Supreme Court, the federal Courts of Appeals, and state appellate courts from around the country. The principal focus, however, is on Massachusetts criminal law and its practice in the courts of the Commonwealth.

Access to the Guide is by annual subscription. If you are not yet a subscriber, please take the tour of a sample chapter from the Guide.

Please Note: If you are an employee of the Massachusetts Trial Court or an Assistant District Attorney, you have unlimited access to the Prosecutor's Guide web site thanks to licenses purchased on your behalf by the Massachusetts Trial Court Law Library and the Massachusetts District Attorneys Association, respectively. Please contact your office law library for access instructions. In the case of ADAs, access to the Guide is through your account on the New York Prosecutors Training Institute website.

Also law students at the following institutions have access through your school Law Library: Harvard, Suffolk, Boston College, Northeastern, Western New England School of Law, New England Law | Boston, Boston University, and the University of Massachusetts.

Please note:
5/21/23: "Motor Vehicle Offenses" has been revised to highlight an important new case, Commonwealth v. Hallinan, which holds out the prospect of a new trial for 27,000 OUI defendants convicted between June of 2011, and April 18, 2019, at least in part with Alcotest 9510 breathalyzer test results. 5/15/23: "Firearms Offenses" has been revised in light of the important new SJC opinion, Commonwealth v. Guardado, placing the burden on the Commonwealth to prove that a defendant did not have a valid license to possess a firearm or ammunition. 4/24/23: "Searches Incident to Arrest" has been updated to include a discussion of the SJC's recent watershed decision in Commonwealth v. Privette, limiting the reach of the horizontal collective knowledge doctrine in ways that Judge Stearns predicts may prove impractical. Please see What's New for further details.

Please note:

5/21/23: "Motor Vehicle Offenses" has been revised to highlight an important new case, Commonwealth v. Hallinan, which holds out the prospect of a new trial for 27,000 OUI defendants convicted between June of 2011, and April 18, 2019, at least in part with Alcotest 9510 breathalyzer test results.

5/15/23: "Firearms Offenses" has been revised in light of the important new SJC opinion, Commonwealth v. Guardado, placing the burden on the Commonwealth to prove that a defendant did not have a valid license to possess a firearm or ammunition.

4/24/23: "Searches Incident to Arrest" has been updated to include a discussion of the SJC's recent watershed decision in Commonwealth v. Privette, limiting the reach of the horizontal collective knowledge doctrine in ways that Judge Stearns predicts may prove impractical.

Please see What's New for further details.