The city of Boston picked up substantial support in its legal battle with the Trump administration as the Massachusetts attorney general, dozens of cities and counties across the country, former law enforcement officials, and advocacy groups filed briefs urging a judge to toss the government’s lawsuit challenging the city’s “sanctuary” immigration policy.
The Boston Trust Act, which limits cooperation between police and federal immigration agents, “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,” Massachusetts Attorney General Andrea Campbell said in a statement after filing the amicus brief in support of the city’s motion to dismiss the case.
In the brief filed Monday in US District Court in Boston, Campbell wrote that the Trust Act complies with state law, including a 2017 ruling by the state’s highest court which found that local law enforcement have no authority to arrest or detain someone solely on the basis of a federal civil immigration detainer.
“Remaining in the United States without lawful status is generally not a crime under federal law, and removal proceedings are civil, not criminal,” Campbell wrote. She noted that the Massachusetts Supreme Judicial Court concluded that “immigration detainers are requests, not commands, and that compliance is voluntary, not mandatory.”
Campbell wrote that the Trust Act “ensures that every Boston resident — regardless of immigration status — can report crimes, serve as witnesses, and seek police assistance without fear that doing so will lead to deportation or other immigration consequences for themselves or loved ones."
The United States has brought multiple suits against so-called sanctuary jurisdictions around the country alleging similar claims, of which two have already been dismissed, one in New York and the other in Illinois, according to Campbell.
In September, the Justice Department sued Boston, arguing that its policies “interfere with the federal government’s enforcement of its immigration laws.”
The suit names the city, the police department, Mayor Michelle Wu, and Police Commissioner Michael Cox.
In a statement announcing the lawsuit, US Attorney General Pam Bondi said, “The City of Boston and its Mayor have been among the worst sanctuary offenders in America — they explicitly enforce policies designed to undermine law enforcement and protect illegal aliens from justice.
Wu has staunchly defended the act.
Last week, the city filed a motion urging US District Judge Leo T. Sorokin to dismiss the case, arguing that the 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 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 a memorandum filed in support of its motion.
The city refuted the government’s claim that the ordinance interferes with the Trump administration’s crackdown on illegal immigration.
“The only burden the Trust Act may incidentally place on the federal government — requiring it to use its own resources to do its own job — is not an impermissible one,“ attorneys for Boston wrote. ”A state or locality declining to participate in a federal regulatory program is not discrimination; it is a sovereign exercise protected by the Tenth Amendment."
The Trust Act says local law enforcement shall not detain people who are eligible for release solely because federal authorities are requesting they be held for civil immigration purposes. It also bars police from asking an individual’s immigration status, sharing personal information about individuals, or notifying federal officials about the date or time someone will be released who is wanted for civil immigration enforcement purposes.
However, the city attorneys wrote, the act explicitly allows police to collaborate with federal officials on criminal matters related to immigration offenses.
The government’s effort to force Boston to assist in its immigration crackdown would force the city to incur significant costs and “divert resources from the criminal law enforcement that keeps Boston safe,” the city wrote in its memorandum.
The Justice Department has not yet filed its response to the motion to dismiss.
The Massachusetts Immigrant and Refugee Advocacy Coalition and the American Civil Liberties Union of Massachusetts filed an amicus brief Monday on behalf of more than a dozen organizations supporting the Trust Act. It cited a number of incidents involving immigrants who had been victims of crime, or were afraid to send their children to school or leave their homes.
An undocumented immigrant who has lived in Boston for 22 years and has two children who are American citizens said, according to the brief, that without the Trust Act, “I wouldn’t be able to go to work peacefully or trust the Boston police when I needed their support, like when I was robbed and all my documents were stolen.”
The brief also described another immigrant, a single mother who has lived in Boston for 25 years, works as a housecleaner, and has a 15-year-old daughter who is an American citizen. She said, “If we don’t have a law that makes me feel safe I would have difficulty taking my daughter to the doctor, to school, or any other place.”
A group of former law enforcement officials, including former Manhattan district attorney Cyrus Vance Jr., also filed an amicus brief, arguing that the Trust Act “does not stop federal officers from enforcing federal immigration laws, but instead simply defines the extent of local involvement.”
They wrote that policies, like Boston’s, allow local law enforcement agencies “to focus their limited resources on their most pressing threats, including violent crime.”
Another brief supporting Boston’s motion to dismiss the suit was filed by 27 cities, counties and elected officials across the country, including Connecticut, New York, Pennsylvania, Illinois, Minnesota, Oregon, California, Texas, Tennessee, and Indiana.
“Many immigrants, regardless of documentation, live in fear, especially during heightened immigration enforcement,” attorneys wrote, adding that it hinders cooperation with police. “This skepticism of law enforcement manifests in concrete ways that make entire communities less safe.”
Shelley Murphy can be reached at shelley.murphy@globe.com. Follow her @shelleymurph.