In a new filing in an ongoing lawsuit over Boston’s “sanctuary” immigration policy, the federal government argues that the city’s policy directs police to “categorically flout” federal immigration authorities “so that removable aliens can evade ICE apprehension,” court records show.
The city’s current course is “obstructionist” and “unlawfully discriminates against the federal government by singling out federal immigration enforcement for unfavorable treatment,“ lawyers for the Department of Justice wrote in a 28-page motion filed Tuesday in federal court in Boston.
The United States has sued several so-called sanctuary cities around the country and brought suit against Boston in September.
The federal lawsuit challenges the Boston Trust Act, alleging that it interferes with federal immigration enforcement.
The suit named the city, the police department, Mayor Michelle Wu, and Police Commissioner Michael Cox.
In November, the city sought to have a judge toss the government’s lawsuit, arguing that the Trust Act neither preempts federal law nor violates the intergovernmental immunity doctrine.
The act, which was adopted in 2014 and amended in 2019, requires the police department “to prioritize criminal law enforcement, while leaving civil immigration enforcement to federal officials,” city attorneys wrote in court filings.
The city’s Trust Act “has been an important component of Boston’s public safety strategy — a strategy that has made Boston the safest major city in the country,” the city’s motion to dismiss said.
Massachusetts Attorney General Andrea Joy Campbell, in November, filed a legal brief supporting the city’s motion to dismiss.
The Trust Act complies with state law, including a 2017 ruling by the state’s highest court, which found that local law enforcement has no authority to arrest or detain someone solely on the basis of a federal civil immigration detainer, Campbell’s brief said.
In a motion filed Tuesday asking a federal judge to deny the city’s motion to dismiss, the government said the Trust Act is an “obstructionist” policy that directs Boston police officers not to ask about immigration status, share information with ICE, make arrests based solely on immigration warrants, perform the functions of immigration officers, or transfer detainees to ICE custody.
“A state may not take action that ‘either frustrates the purpose of the national legislation or impairs the efficiency of th[e] agencies of the federal government to discharge the duties for the performance of which they were created,’” government lawyers wrote in the motion.
Tonya Alanez can be reached at tonya.alanez@globe.com. Follow her @talanez.