President-elect Donald Trump repeatedly clashed with Democratic cities and states that adopted policies offering sanctuary to undocumented immigrants during his first term. Now, both sides are gearing up for round two. During Trumps first term, sanctuary cities refused to allow local law enforcement to share information with federal immigration agents or hand over immigrants in their custody. This time around, many are planning to do the same, even if doing so draws them into a fight with the second Trump administration.Trumps so-called border czar Tom Homan, a fellow at the conservative Heritage Foundation and a named contributor to its Project 2025 manifesto, has indicated the incoming administration plans to make sanctuary jurisdictions targets for mass deportations. Homan said recently he hopes that local law enforcement will cooperate with requests from US Immigration and Customs Enforcement (ICE) to hand over undocumented immigrants already in their custody, especially when they pose a public safety threat. What mayor or governor doesnt want public safety threats out of their communities? he told the Center Square. Their No. 1 responsibility is to protect their communities. Thats exactly what we are going to do.Most Democratic leaders, however, have made it clear that they will not accept federal government overreach on deportations and that they are preparing to challenge Trumps immigration policies in court. Were not looking for a fight from the Trump administration, but if he attacks our progress, well fight back, California Attorney General Rob Bonta told Vox. Immigrants are such a critical part of who we are who we will be.How Trump targeted sanctuary cities in his first termIn his first term, Trumps crackdown on sanctuary jurisdictions took two forms: attempting to withhold federal funding from them and challenging their policies in court.In 2017, the Trump administration sought to block sanctuary cities from receiving federal law enforcement grants. A number of Democratic state attorneys general sued, including on behalf of New York state and city, Connecticut, New Jersey, Washington, Massachusetts, and Virginia. Three appeals courts reached different conclusions on those legal challenges, setting up a US Supreme Court fight in 2020. After Trump lost the election that year, however, the Supreme Court dismissed the case at the request of the Biden administration.That left the underlying legal questions in the case unresolved. However, Muzaffar Chishti, a senior fellow at the Migration Policy Institute and director of its office at New York University School of Law, said that the Constitutions 10th Amendment protecting states rights provides a strong defense for sanctuary cities and states going forward.I dont think the last word on this issue from the Supreme Court has been heard, he said. The 10th Amendment is the best defense that states and localities still have as to why they shouldnt be penalized because theyre not fully cooperating with the federal government.The Trump administration also challenged several California state laws in court, arguing the laws interfered with the administrations federal immigration enforcement agenda and were unconstitutional.One of those laws was the California Values Act, signed by Democratic Gov. Gavin Newsom in 2017. The law prevents state and local police and sheriffs from cooperating with federal immigration authorities in a number of ways: They cannot ask about an individuals immigration status, arrest an individual on the basis of most immigration violations alone, share an individuals personal information with federal immigration agents unless otherwise publicly available, hand someone in local police custody over to federal immigration agents (with some exceptions), and more. Another California law challenged by the Trump administration was the Immigrant Worker Protection Act, which barred businesses from sharing employee records with immigration agents absent a court order or a subpoena. It also required employers to provide notice of upcoming inspections of workers employment authorization documents, given that undocumented immigrants do not have valid ones. An appeals court ultimately upheld the Values Act but struck down the parts of the Immigrant Worker Protection Act prohibiting record-sharing. The US Supreme Court refused to hear the Trump administrations appeal of that ruling at the time, meaning the ultimate constitutionality of the law remains unsettled. That means Trump could revive and expand the tactics he used to target sanctuary cities last time, and its not clear whether they would hold up in court, setting the stage for a new round of legal battles in the years to come. What Trump could do in his second termTrump is again preparing to punish sanctuary jurisdictions interfering with his immigration agenda. Homan suggested on a recent appearance on the talk show Dr. Phil that the incoming administration would go as far as to prosecute people who attempt to impede federal immigration enforcement. If you knowingly conceal or harbor an illegal alien from a police officer, it is a felony. To impede a federal law enforcement officer is a felony, so dont cross that line, he said. We will present these prosecutions, so you know, dont test us!Trumps advisers are also reportedly discussing reviving and expanding his previous attempt to condition federal funding to Democratic cities on cooperation with federal immigration agents. While his first administration focused on law enforcement grants, some in his circle are hoping to tackle other streams of funding, too. There is a potentially wide range to consider as cities and states get federal money for everything from infrastructure to education.Not an iota, not a cent of government spending, should go to subsidize this, Vivek Ramaswamy, Trumps pick to co-chair his new Department of Government Efficiency, told ABC last month. Not to sanctuary cities, not to federal aid to people who are in this country illegally.Trump would likely be limited in efforts to withhold funding by a 1974 law that restricts the presidents ability to cancel government spending unilaterally. If Trump were able to convince Congress to overturn that law or successfully challenges it in court, however, he would likely have more leeway to restrict funding to sanctuary cities without congressional approval. Trump is also reportedly looking to revoke agency policy preventing ICE arrests at sensitive locations, including schools and churches. He could do so unilaterally on his first day in office.How sanctuary cities and states are respondingMany mayors and attorneys general in blue states have lined up in support of sanctuary policies heading into Trumps second term. Bonta has already pledged to take the administration to court if it tries to withhold funding to sanctuary jurisdictions again.It was an unconstitutional attempt to coerce California against its states rights, he said. If they attempt to do that again, well bring them to court again, and we will argue that our 10th Amendment rights, our states rights, prevent such conditioning of grant funding to us.Bonta also said that any attempt Trump makes to deport US citizens together with their undocumented family members something the president-elect has floated would be unconstitutional and that his mass deportation plan is bound to violate individuals due process rights. Most Democratic leaders have echoed Bontas statements, but there is one notable exception: New York City Mayor Eric Adams, who has expressed willingness to work with the Trump administration on its deportation goals. Adams is reportedly considering working with the Trump administration to target violent individuals. He has insisted he would not go further than that, but immigrant rights groups have raised concerns that he might anyway, worried that the mayor will leave New York Citys half-a-million undocumented immigrants more vulnerable to deportation than they were last time Trump was president.Mayor Adams has repeatedly demonized undocumented immigrants, from implying that they can be stripped of their right to due process to using them as scapegoats for his mismanagement of the City budget, the group Make the Road NY said in a statement.Adams told Fox that his legal team will sit down with the president-elects to explore the possibility of an executive order that could override New York Citys sanctuary laws. Those laws currently place limits on information-sharing with federal immigration authorities and prevent the city from honoring requests from ICE to detain people. He also said that his administration is looking into exceptions to New York City law preventing any ICE officer from entering a city government building. That would potentially allow ICE to access the city jail on Rikers Island, as Homan has requested.Adamss posture is a reflection of the changing politics of immigration among Democrats in recent years after apprehensions at the southern border reached record highs and many blue cities strained to absorb immigrants arriving on buses from border states. Under Biden, Democrats embraced a right-wing border security bill that represented a sharp turn from their emphasis on immigrants rights and contributions to the country.This three and a half years of border arrivals left a long shadow on the immigration policy and politics of our country in a way not fully appreciated, Chishti said. To say that we should welcome every immigrant in our city is not where the center of gravity of the Democratic Party is today.While other Democrats arent as vocal as Adams in supporting cooperation with the incoming Trump administration, others havent been as full-throated in their support of sanctuary policies. Philadelphia Mayor Cherelle Parker, for instance, said last month that she did not know what would happen in the future to the citys sanctuary policies, even though a spokesperson for her office told Vox that those policies remain in place for now. That tepid commitment suggests the ground may be shifting even outside of New York City.Youve read 1 article in the last monthHere at Vox, we're unwavering in our commitment to covering the issues that matter most to you threats to democracy, immigration, reproductive rights, the environment, and the rising polarization across this country.Our mission is to provide clear, accessible journalism that empowers you to stay informed and engaged in shaping our world. By becoming a Vox Member, you directly strengthen our ability to deliver in-depth, independent reporting that drives meaningful change.We rely on readers like you join us.Swati SharmaVox Editor-in-ChiefSee More: