On November 15, 2022, the Civil Rights Division of the Department of Justice and the Office of U.S. Attorney for Massachusetts Rachel S. Rollins announced the start of a “Pattern-or Practice” investigation of the Worcester Police Department.

This brief serves as a primer for:

1. The history of the 78 pattern-or-practice investigations under 34 U.S.C. § 12601, including information about when, where, and whether those investigations have been resolved.
2. The process of those investigations, including what the Department of Justice examines during its investigation, as well as the procedure for concluding them.
3. The outcomes that have come from previous investigations, including 22 memoranda of Research in the Public Interest understanding, 21 consent decrees, 16 resolutions through technical assistance letters or private litigation, and 10 cases closed without any findings or agreements.

This brief does not make any conjectures about what prompted the Department of Justice investigation, but rather aims to educate the public about what we know about the process, its potential length, and the types of outcomes that may come from it.