A federal appeals court will decide whether to revive a lawsuit brought by President Donald Trump that sought to invalidate state, city and county laws designed to protect undocumented immigrants by prohibiting local law enforcement officials from helping federal agents.
A three-judge panel from the 7th Circuit Court of Appeals on Thursday heard oral arguments and peppered attorneys from the U.S. government, state of Illinois, Cook County and city of Chicago with questions as it weighs whether to overturn the dismissal of that lawsuit.
The panel did not issue any ruling following Thursday’s hourlong hearing at the Dirksen Federal Building in downtown Chicago.
The appeal comes more than a year after a federal judge tossed out the Trump administration’s case, and in doing so refused to invalidate the state, city and county laws designed to protect undocumented immigrants in Chicago by prohibiting local law enforcement officials from helping federal agents.
The Trump administration’s lawsuit argued that Chicago’s Welcoming City ordinance and the Illinois Trust Act reflect “an intentional effort to obstruct the Federal Government’s enforcement of federal immigration law and to impede consultation and communication between federal, state, and local law enforcement officials that is necessary for federal officials to carry out federal immigration law and keep Americans safe.”
Attorneys representing the Trump administration in their appeal argued the policies reject the federal system of immigration enforcement “in favor of one defendants created” and are discriminatory because they “single out federal immigration officials.”
“The Sanctuary Policies represent an open assault on the federal government’s plenary authority over immigration,” they wrote in a court filing.
Department of Justice attorney Michael Talent on Thursday used the example of federal agents, who are barred from entering detention facilities across Illinois, having to try and stake those facilities out to detain undocumented persons when they’re released from custody because local authorities are barred from sharing information with them.
He argued this creates “dangerous and difficult” situation for agents, who must try and detain them on a public street instead of having them transferred directly into their custody to begin the removal process.
But the appellate judges questioned whether Illinois or any other state has any required duty to cooperate with federal immigration agents.
Judge Rebecca Taibleson on Thursday noted Congress has been “a little bit cute or cagey” about defining what exactly states are required to do with regard to information and custody handovers.
But she added that the current immigration laws “clearly stopped short of requiring” such action.
“Given that,” she said, “it’s a bit much to ask us to transform this sort of ambiguity into a mandate through the mechanism of conflict preemption.”
Alex Hemmer, Illinois’ deputy solicitor general, agreed, stating that Illinois has chosen not to task police with enforcing federal immigration, and that nothing in the Immigration and Nationality Act (INA) requires them to do so.
“Nothing in the text or structure of the INA requires states to pledge police resources to the enforcement of federal immigration law, to execute immigration detainers, transfer state prisoners to federal custody or respond to federal investigative inquiries regarding those prisoners,” he said.
Chicago’s Welcoming City ordinance is designed to ensure that all Chicago residents, regardless of their citizenship or immigration status, can obtain city services, including police protection and medical care.
U.S. District Court Judge Lindsay Jenkins’ July 2025 decision to dismiss the Trump administration lawsuit request sought by Chicago Mayor Brandon Johnson and Illinois Gov. JB Pritzker without holding a full trial marked a major victory for officials seeking to prevent federal officials from slashing billions of dollars in federal aid to Chicago and Illinois.
Forcing Chicago and Illinois law enforcement officials to help federal agents conduct deportation operations is unconstitutional, Jenkins ruled at the time, stating that it would “allow the federal government to commandeer States under the guise of intergovernmental immunity — the exact type of direct regulation of states barred by the Tenth Amendment.”
WTTW’s Heather Cherone contributed to this report.
