Massachusetts voters will decide Nov. 3 whether to keep a 2024 law that expanded firearm regulations, including requirements for privately made guns and new ways to petition courts to temporarily remove firearms from people deemed dangerous. Question 9 is a referendum on the law, known as Chapter 135, which Gov. Maura Healey signed in July 2024 after the Legislature approved it. A yes vote keeps the law in place; a no vote repeals it. Gun-rights advocates gathered enough signatures to put the repeal question on the ballot. The law requires privately made firearms, including so-called ghost guns, to have serial numbers. It also allows school administrators and health care providers to ask courts to issue red-flag orders. Semi-automatic rifles and shotguns are limited to people 21 and older, and the law restricts carrying firearms in schools, polling places and government buildings. It also sets rules for assault-style firearms, requires electronic registration and adds training on topics including suicide prevention, use-of-force law and conflict avoidance. The state’s registration and serialization deadline is Oct. 28, six days before the election. Supporters say the law updates Massachusetts rules to address newer firearm technology and strengthens tools to prevent suicide. Opponents have raised constitutional concerns and cited compliance and training costs, as well as added burdens on local police. A September MassINC poll found 70% of respondents favored keeping the law, 18% supported repealing it and 11% were undecided. The figures total 99%, apparently because of rounding. Repealing Chapter 135 would not eliminate the bulk of Massachusetts’ existing gun regulations, including licensing and safety-training requirements and the state’s earlier assault-weapons ban.