In January 2017, President Donald Trump issued an executive order granting the attorney general of the United States broad discretion "to ensure" that "sanctuary jurisdictions…are not eligible to receive federal grants." Six months later, Attorney General Jeff Sessions wielded that power by declaring the Byrne Memorial Justice Assistance Grant Program, which provides a wealth of federal dollars to local law enforcement agencies, to be off-limits to any jurisdiction that refuses to "comply with federal law, allow federal immigration access to detention facilities, and provide 48 hours notice before they release an illegal alien wanted by federal authorities."
It was an aggressive move. Unfortunately for the Trump administration, it also happened to be an unconstitutional one. The executive branch, of which the attorney general is a part, has no lawful authority to unilaterally impose such conditions on federal spending. The federal spending power rests in Article I of the Constitution, which is the section that lays out the enumerated powers of Congress. The enumerated powers of the executive are spelled out separately in Article II. Sessions' maneuver, in other words, usurped congressional authority and thus violated the separation of powers. Trump can issue all of the executive orders he wants, but he cannot alter this basic fact about the American constitutional system.
In a ruling issued last month, the U.S. Court of Appeals for the 7th Circuit recognized the Trump administration's malfeasance for what it is. "The Attorney General in this case used the sword of federal funding to conscript state and local authorities to aid in federal civil immigration enforcement," the 7th Circuit observed in Chicago v. Sessions. "But the power of the purse rests with Congress, which authorized the federal funds at issue and did not impose any immigration enforcement conditions on the receipt of such funds. In fact," the court pointed out, "Congress repeatedly refused to approve of measures that would tie funding to state and local immigration policies." To allow the Trump administration to act in this manner, the 7th Circuit concluded, would be to remove a "check against tyranny."
This was not the first time that the Trump administration's attack on sanctuary cities has received a well-deserved judicial rebuke. In November 2017, the U.S. District Court for the Northern District of California found Trump's executive order to be in violation of both the separation of powers (because it sought to expropriate congressional spending authority) and the 10th Amendment (because it tried to force local police into administering a federal regulatory program).
Make no mistake, these cases are about much more than just immigration policy. The Trump administration seeks to impose its will on this issue by aggrandizing the executive, trashing federalism, and subverting the separation of powers. Such unconstitutional tactics should always lose in court.