San Francisco sued the Trump administration on Tuesday, charging that its crackdown on sanctuary cities violates the state rights provisions of the U.S. Constitution.
The filing in federal court comes less than a week after President Trump issued orders putting cities and counties on notice that they would lose federal funding if they did not start cooperating with immigration agents.
The move has broad implications for California, a state that aggressively protects immigrants who are in the country illegally from deportation.
San Francisco, one of 400 sanctuary cities and counties in the country, stands to lose more than $1.2 billion a year in federal funding, most of it for healthcare, nutrition and other programs for the poor, according to San Francisco City Atty. Dennis Herrera.
"The president's executive order is not only unconstitutional, it's un-American," Herrera said. "That is why we must stand up and oppose it. We are a nation of immigrants and a land of laws. We must be the 'guardians of our democracy' that President Obama urged us all to be in his farewell address."
The cities Trump is targeting have many tools to strike back. Among the most potent are high court decisions that have interpreted financial threats such as the one Trump is now making as an unlawful intrusion on states' rights.
New York Atty. Gen. Eric T. Schneiderman also announced Tuesday that New York would join a lawsuit filed by the ACLU against Trump over the sanctuary city directive.
"I will continue to do everything in my power to not just fight this executive order, but to protect the families caught in the chaos sown by President Trump's hasty and irresponsible implementation," Schneiderman said in a news release.
Trump has called for local officials to report to immigration officers people who are in jail and could be deported when they are released.
The issue of local cooperation with immigration officials came into the national spotlight after Kathryn Steinle, 32, was shot to death in July 2015 on a pier at San Francisco's Embarcadero.
The man arrested in her death, Mexican national Juan Francisco Lopez-Sanchez, had been jailed on an immigration law violation after returning to the United States despite being deported five times. He was released from custody months before the shooting after San Francisco prosecutors decided not to pursue a decades-old bench warrant in a marijuana case.
Trump described the murder as "a senseless and totally preventable violent act committed by an illegal immigrant."
San Francisco's lawsuit contends that Trump's executive order violated the 10th Amendment, which established a balance of power between the federal government and states.
"The Executive Branch may not commandeer state and local officials to enforce federal law," the lawsuit stated.
Herrera described Trump's action as a "wild overreach."
"This country was founded on the principle that the federal government cannot force state and local governments to do its job for it, like carrying out immigration policy," Herrera said.
The lawsuit stated that federal funds make up 13% of the city's budget and asks that Trump's directive be blocked immediately.
San Francisco's sanctuary law prohibits local law enforcement officers from cooperating with Immigration and Customs Enforcement detention requests and limits when the officers may notify the federal agency of a person's release from jail.
The lawsuit argued that the purpose of the sanctuary law was to protect children, not criminals, and to ensure that parents in the country without a green card can bring their children to schools and to doctors.
The law prohibits San Francisco officials from holding an individual who is eligible for release from jail on the basis of a civil immigration detention request from the federal government. The city does honor criminal warrants, the suit said.
"Strong cities like San Francisco must continue to push the nation forward and remind America that we are a city that fights for what is right," Mayor Ed Lee said.
UC Irvine Law School Dean Erwin Chemerinsky, a constitutional law professor, said the Supreme Court has interpreted that the Constitution prevents the federal government from commandeering state and local governments to administer a federal law.
In 1997, the conservative majority on the high court ruled that the federal government could not force states to do background checks prior to gun sales. The late Justice
In a 2012 ruling on Obamacare, the court decided 7 to 2 that the federal government could not threaten states with loss of money for failing to comply with a Medicaid requirement.
Chemerinsky said the rulings strongly bolster lawsuits filed on behalf of sanctuary cities against Trump.
"The federal government can't force local governments to administer a program under the threat of losing federal money," Chemerinsky said.
Trump left unclear what funding is at stake and which cities and counties are threatened. The administration would be on shaky legal ground going after money allocated for anything other than law enforcement, and taking funds away from police is a risky proposition for a new president promising to restore order in the streets. And even that, attorneys for the Legislature assert, takes an act of Congress.
More than 400 jurisdictions across the country have some sort of policy regarding how they deal with people in the country illegally, including Los Angeles, San Francisco and about 40 others in California.
There is no neat definition of a sanctuary city, but in general, cities that adopt the designation seek to offer political support or practical protections to people who are in the country illegally.
For some cities, the sanctuary movement consists simply of encouraging people without legal status to get more involved in government. For instance, Huntington Park has never declared itself a sanctuary city, but it appointed two people without legal status to a city commission, a move that generated national attention.
Other places, such as San Francisco, adopt far-reaching policies, such as taking steps to cut ties with federal immigration officials and refusing to fully cooperate with them. San Francisco declared itself a sanctuary city in 1989, and city officials strengthened the stance in 2013 with its "due process for all" ordinance. The law declared that local authorities could not keep immigrants in custody to be handed over to federal immigration officials if they had no violent felonies on their records and did not face charges.
San Francisco's lawsuit comes amid growing rancor over Trump's orders, which include restrictions on travel from some Muslim-majority countries and plans to build a wall along the U.S.-Mexico border.
2:20 p.m.: This article was updated with additional information on sanctuary cities.
12:05 p.m.: This article was updated with more details about San Francisco's sanctuary city history and a quote from the mayor.
10:50 a.m.: This article was updated with new information about the lawsuit, comment from San Francisco's city attorney and larger context about sanctuary cities.