Redistricting authority:
U.S. Congressional Districts – Legislative. There is no statutory framework for congressional redistricting in Massachusetts.  By default it follows Massachusetts’ legislative redistricting process: The General Court of Massachusetts (their General Assembly) is in charge of districting the Commonwealth into legislative districts, and they must begin doing so by the third January following the taking of the decennial census.  The Governor may veto plans passed by the Legislature. The Constitution does not address what happens if the Legislature doesn’t pass a plan in time.

State Legislative Districts – Legislative. The General Court of Massachusetts (their General
Assembly) is in charge of districting the Commonwealth into legislative districts, and they must
begin doing so by the third January following the taking of the decennial census. The Governor
may veto plans passed by the Legislature. The Constitution does not address what happens if the
Legislature doesn’t pass a plan in time.