“Over the past three months, the Trump administration has filed lawsuits against Los Angeles, Illinois, Colorado, New York state, New York City, and other places for the express purpose of forcing them to abolish their “sanctuary city” policies and start aiding the feds in rounding up undocumented immigrants and enforcing federal immigration laws.
But unless the U.S. Supreme Court rapidly overturns several of its own precedents, including a recent one from 2018, all of these cases will be constitutional losers for President Donald Trump. Why? Here is how the late conservative legal hero and long-serving Supreme Court Justice Antonin Scalia once spelled it out.
“The Federal Government may neither issue directives requiring the States to address particular problems,” Scalia wrote for the Court’s majority in Printz v. United States (1997), “nor command the States’ officers, or those of their political subdivisions, to administer or enforce a federal regulatory program.”
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federal agents still retain their own independent authority to enforce federal immigration law inside of sanctuary states and cities, just as federal authorities retain the independent authority to enforce other federal laws in states and cities. The key point under Printz is that it is unconstitutional for the feds to compel local officials to lend them a helping hand in carrying out the enforcement of federal law.”
https://reason.com/2025/07/31/on-sanctuary-cities-its-trump-vs-the-10th-amendment