BOSTON — On Monday, Nov. 24, 2025, Massachusetts Attorney General Andrea Joy Campbell filed an amicus brief supporting the City of Boston’s motion to dismiss a case brought by the Department of Justice last September challenging the legality of the Boston Trust Act, a city ordinance that limits the participation of state and local officials in federal civil immigration enforcement. The filing comes after the U.S. Department of Justice sued the City of Boston in September, arguing that the law violates federal immigration statutes and the Constitution’s Supremacy Clause.
Trump's DOJ is suing @CityOfBoston over the Trust Act – a local law that limits law enforcement's participation in federal immigration policy, builds trust, & promotes public safety.
— AG Andrea Joy Campbell (@MassAGO) November 25, 2025
I'm filing a brief with the courts today to stand with Boston, the safest major city in America.
According to the DOJ’s complaint filed on September 4, 2025, in the U.S. District Court for Massachusetts, Boston’s ordinance “directs the Boston Police Department not to cooperate with federal immigration enforcement” by requiring “Boston police officers to refuse federal immigration detainers—a document by which the government provides notice of its intent to assume custody of a removable alien detained in the custody of another law enforcement agency—which are essential to enforcing immigration law.”
In a statement, Boston Mayor Michelle Wu described the lawsuit as “an unconstitutional attack on our city” and defended the policy as critical to building trust between law enforcement and immigrant communities.
We will not yield.
— Office of Mayor Michelle Wu 吳弭 (@mayorwu.boston.gov) September 4, 2025 at 8:32 PM
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AG Campbell argued that the Trust Act supports public safety by allowing immigrants to report crimes, serve as witnesses and engage with public services without fear of deportation — a position aligned with Massachusetts precedent.
“The Trust Act promotes public safety and fosters trust between local law enforcement and the communities they serve, helping to make Boston the safest major city in America,” AG Campbell said. “I am proud to stand with the city of Boston against this egregious attempt at federal overreach, as we work to protect the rights of all municipalities to set local policy like the Trust Act, that is consistent with state and federal law.”
In its motion to dismiss, the City of Boston argues that the Boston Trust Act simply governs the city’s own use of local resources and does not obligate federal immigration enforcement, asserting that the federal government cannot force cities to deploy local law-enforcement resources for civil immigration detainers under the Tenth Amendment. The filing contends the federal complaint mischaracterizes the ordinance as obstruction of federal law when in fact the city is choosing how to allocate its personnel and funding, and that this policy has helped foster community trust and public safety without interfering with federal immigration operations.
The DOJ’s lawsuit pits principles of local autonomy and community policing against federal obligations and immigration enforcement. If the federal government prevails, it could threaten sanctuary-style policies nationwide. If Boston succeeds, it may reinforce municipal discretion in immigration cooperation.
