Democratic mayors of four major cities said Wednesday that Congress and the Trump administration are exaggerating crime committed by immigrants and attacking so-called sanctuary cities simply to score political points, as Republicans hammered the policies for shielding criminals and discouraging cooperation with federal officials. The comments came in a hearing before the House Committee on Oversight and Government Reform, where Republicans accused the mayors of putting their cities in danger and undermining President Donald Trump’s mass deportation efforts. Republicans have repeatedly highlighted crimes committed by immigrants who crossed illegally into the U.S., with Rep. James Comer opening the hearings by saying the policies “only create sanctuary for criminals.” But the Democratic mayors — Michelle Wu of Boston, Brandon Johnson of Chicago, Mike Johnston of Denver and Eric Adams of New York — pushed back hard, even as they seemed to carefully avoid using the term “sanctuary.” “We know there are myths about these laws. But we must not let mischaracterizations and fear mongering obscure the reality that Chicago’s crime rates are trending down,” Johnson told committee in a hearing room packed with reporters and onlookers. “We still have a long way to go, but sensationalizing tragedy in the name of political expediency is not governing. It’s grandstanding.”

There’s no legal definition for sanctuary city policies, but they generally limit cooperation by local law enforcement with federal immigration officers. Courts have repeatedly upheld the legality of sanctuary laws.

Adams noted that New York’s sanctuary policies do not allow the city to violate immigration law or hinder enforcement. “New York City will always comply with city, state, and federal laws as it does now,” he said. Adams got some of the only praise from Republican lawmakers, with Comer thanking him for working with Immigration and Customs Enforcement.

Adams’ critics say his collaboration is part of an effort to wriggle out of federal corruption charges, though even before Trump was elected, the mayor called on city lawmakers to allow New York police to work more with ICE. The Trump administration ordered prosecutors to drop the case on the grounds that it was distracting Adams from helping the immigration crackdown and hindering his reelection campaign. About two hours into the hearing, Democratic lawmakers began questioning him sharply over his work with the Trump administration and the dropped charges. “Are you selling out New Yorkers to save yourself from prosecution?” asked Rep. Robert Garcia, of California. “There’s no deal, no quid pro quo. And I did nothing wrong,” Adams said. Denver’s Johnston said that crime decreased when the city was faced with an influx of immigrants, many bussed from border states by Republican politicians. Like the other mayors, he also called for immigration reform that would make it easier for people to legally enter the U.S. “If Denver can find a way to put aside our ideological differences long enough to manage a crisis we didn’t choose or create, it seems only fair to ask that the body that is actually charged with solving this national problem — this Congress — can finally commit to do the same,” he said.

Immigration laws, the mayors said, is a federal responsibility, and the attempt to put that responsibility on local law enforcement simply makes communities distrust the police and others they may need to call for help. “This federal administration’s approach is undermining that trust,” said Wu, whose parents immigrated to the U.S. from Taiwan. “This federal administration is making hard-working, taxpaying, God-fearing residents afraid to live their lives.” “You belong here,” Wu said, addressing immigrant communities in Boston. “This is your home.” The Republican majority last week released a nearly three-minute-long video previewing the hearing. It opens with images of the Constitution catching fire and burning, revealing photos of the four mayors. It goes on to show arrests by ICE agents of people who’d committed crimes in those cities interspersed with comments from the mayors and news stories showing negative impacts of migration surges.

The video ends with Comer threatening to cut the cities’ federal funding if they don’t cooperate with immigration enforcement. In communities that don’t cooperate on immigration, ICE agents go in to track down people after their release. ICE argues that this is dangerous and strains resources. Ohio Republican Rep. Jim Jordan grilled Johnston for a Denver arrest that he said required ICE agents to apprehend a man recently released from local custody, and mocked Johnston’s insistence that his city was safe. “That’s a lie because it was not safer for the ICE agents who are part of your community. No way was it safer,” he said.

Trump administration officials have also argued that if communities work with them on immigration enforcement, “collateral arrests” — when ICE detains people other than those targeted — are less likely. “Sanctuary cities want to keep locking us out of jails,” Trump’s border czar, Tom Homan, told reporters recently. “They force us into the neighborhood to find the bad guys. When we find the bad guy, many times they’re with others.” Advocates say that while ICE claims to target “the worst of the worst” — meaning immigrants who’ve committed heinous crimes in the U.S. — they end up going far beyond that, destabilizing communities. But the Trump administration continues to target them and has sued Chicago and Illinois as well as New York state over various immigration laws.