Passed by the Maine Legislature in June 2025 and allowed to become law without Gov. Mills’ signature on January 11, 2026, LD 1971 prohibits state, county, and local law enforcement agencies from engaging in most forms of cooperation with federal civil immigration enforcement. Mills simultaneously repealed a 2011 executive order that had directed state officials to cooperate with federal immigration authorities. Passage of LD 1971 followed a documented case in which local Maine police detained and transferred vehicle occupants to Border Patrol custody at another agency’s request — a transfer the ACLU of Maine says would likely be unlawful under LD 1971.