On Wednesday, President Donald Trump signed an executive order that could pull federal funding from so-called "sanctuary jurisdictions" like Boston that, in the order's words, "willfully violate federal law in an attempt to shield aliens from removal from the United States."
Boston Mayor Marty Walsh responded with defiance after Trump's announcement, vowing to shelter undocumented immigrants in his City Hall office if need be. "If people want to live here, they’ll live here. They can use my office. They can use any office in this building," Walsh said as he stood flanked by city officials.
That stance could put $501 million in federal funds to various city departments on the line, but experts disagree over whether the federal government has the legal authority to follow through on that threat.


"The federal government can't demand that state officials or local officials do their work," Barry Friedman, director of New York University's Policing Project, told NPR.

“It appears to me, based on my review from case law, that there are severe limits on the federal government’s ability to control state and local entities by controlling the purse strings,” Susan Church, of the American Immigration Lawyers Association, told The Boston Globe.

Other experts disagree. The administration can use its vast federal spending powers to bring cities in-line with its interpretation of the law, according to Jessica Vaughan of the Center for Immigration Studies, who has advised the Trump administration.

"The Trump administration can largely get the results it is seeking and a real meaningful end to most of these sanctuary policies through a combination of carrots and sticks," Vaughan told USA Today.

The thorny legal issues involved could mean a long legal battle. In the meantime, Boston could stand to lose around $501 million in federal funding for public housing, schools, and other city departments, according to projections provided by the city for fiscal year 2017. Below is a breakdown of what that money is budgeted for.



WGBH News reporter Tina Martin contributed to this story.