The U.S. government filed a lawsuit against the city of Milwaukee Thursday, arguing the city has no authority to enforce its ordinance preventing law enforcement from wearing masks while interacting with the public. 

The lawsuit, filed against the city as well as its mayor, city attorney and police chief, argues that cities and states are unable to regulate federal government action. 

“For centuries, the Supreme Court has reaffirmed that States have no authority whatsoever to regulate the Federal Government,” the lawsuit states. “Despite that well-established principle, Milwaukee recently enacted an ordinance that purports to do exactly what constitutional law says it cannot: regulate how federal law enforcement officers carry out their official duties in that City.”

Initially enacted in April, the Milwaukee ordinance prohibits law enforcement officers performing their duties from covering their faces and requires that their names and the agency they work for be easily identifiable on their uniform. 

“The use of facial coverings and disguises by law enforcement officers significantly affects the public’s perception of law enforcement, officer-community interactions, and accountability,” the ordinance states. “Persons reasonably may experience fear or intimidation when approached by officers whose faces are obscured. Such reactions can heighten defensive behavior and unnecessarily escalate the tension inherent in many interactions between law enforcement officers and members of the public.”

Last week, City Attorney Evan Goyke wrote in a letter to U.S. prosecutors  that federal officers wouldn’t be exempted from the ordinance, prompting the lawsuit. 

“the City and the public have a right to know if masked, armed, and unidentified men seizing people on our streets are who they say they are,” Goyke wrote, objecting to the federal government’s insistence that immigration officers be allowed to conceal their identities “at their discretion.”

“Unfortunately, in the case of federal immigration officers, in particular, that unbounded discretion, coupled with guns and a lack of accountability, has had tragic consequences in cities across the country,” he wrote. Goyke disputed the federal government’s claim that the Supremacy Clause of the U.S. Constitution makes ordinances such as Milwaukee’s illegal, citing previous and ongoing litigation on the matter.

Federal immigration officers across the country have worn masks while carrying out  President Donald Trump’s crackdown on immigrants. Federal officials have argued the masks prevent officers from being doxxed. 

“State and local leaders cannot tell Federal officers how to do their job,” Associate Attorney General Stanley E. Woodward, Jr. said in a news release. “And they certainly cannot prohibit them from ensuring their own safety in safeguarding our communities and enforcing federal law. We will never tolerate the doxxing or harassment of federal officers, or any law like Milwaukee’s that enables violent behavior against law enforcement officers and their families.”

The lawsuit argues that federal officers should be able to make decisions about covering their faces on a case-by-case basis. 

“Denying federal agencies and officers discretion in these areas would chill federal law enforcement, threatening the safety of communities in Milwaukee,” the lawsuit states.

Brad Schimel, the former conservative Supreme Court candidate who is now an assistant U.S. attorney, said that the ordinance pits federal and local cops against each other. 

“Not only is this ordinance an affront to the Constitution, but it jeopardizes the safety of our courageous sworn law enforcement officers,” Schimel said. “Further, it puts local and federal law enforcement officers at odds with each other when they should be working together on the common goals to enforce the rule of law and keep our communities safe.”

The Justice Department rejected Milwaukee’s attempts to prohibit immigration agents from wearing masks in a Friday letter to Milwaukee Mayor Cavalier Johnson and City Attorney Evan Goyke. “We write to seek assurances that neither your offices, the Milwaukee Police Department, nor any other entity in Milwaukee plans to enforce Milwaukee Code ordinances…(“Mask Ban” or “Ordinance”) against federal law enforcement officers,” the letter, signed by Assistant Attorney General Brett Shumate and U.S. Attorney for the Eastern District of Wisconsin Brad Schimel, states. “The enforcement of such a law would be unconstitutional under the Supremacy Clause.”

The Supremacy Clause in Article VI  of the United States Constitution holds that federal law overrides state and local laws. “Unfortunately, some states and localities have seemingly forgotten this bedrock principle of American law, passing so-called ‘sanctuary policies’ to impede federal immigration enforcement and going so far as to even directly regulate federal law enforcement in the performance of their official duties, ” the letter states. “This is precisely what Milwaukee has done with its Mask Ban.”

Over recent weeks, as immigration arrests have escalated, Milwaukee officials developed a package of city ordinances designed to regulate the behavior of federal agents in the city. One of those ordinances prohibits  agents from wearing masks, with elected leaders and advocates arguing that residents should not be confronted by masked men in unmarked cars and without badges or other clear proof that they are law enforcement officers. 

The letter states that agents require the now notorious masks, which cover the entire face and are often paired with dark sunglasses and caps, to prevent the public from identifying them and then harassing them or their families. “Some doxxing and harassment incidents have resulted in federal charges,” the letter states. “The modification of uniforms to prevent identification also prevents suspects from identifying officers and taking preemptive actions to evade apprehension or obstruct enforcement efforts.” 

The letter cites a Department of Homeland Security (DHS) press release which claimed that immigration officers have faced an 8000% increase in death threats against them and their families. Compelling federal immigration agents to be identified like any other law enforcement officer “potentially exposes federal officers to enforcement against them in the performance of their federal duties, chilling their ability to perform those duties,” the letter states. “And it raises the specter of a confrontation between local and federal law enforcement.”

The letter blasts  Johnson, saying that the mayor “has deplorably compared our brave federal agents enforcing federal law to the ‘Gestapo.’” It demanded an assurance from city officials that they will not enforce the mask ban by July 17. 

Johnson is among many local officials in Milwaukee and across the country who have denounced the Trump administration’s immigration crackdown, especially after agents killed Renee Good and Alex Pretti during the ICE surge in Minneapolis. Recently, ICE officers shot and killed a Mexican man in Houston, Texas, who had lived in the United States for 35 years, working to send his three U.S.-born sons to college. The man, Lorenzo Salgado Araujo, had no criminal record, and his family is demanding an independent probe, saying the federal government’s charge that he tried to drive his car into ICE agents is false. 

This week U.S. Rep. Gwen Moore joined Mayor Johnson, state Sen. Tim Carpenter (D-Milwaukee), state Rep. Sylvia Ortiz-Velez (D-Milwaukee), and other elected and community leaders in denouncing the surge in immigration arrests in Milwaukee with 57  people apprehended over three days. One of the people agents arrested, who was later released, described agents insulting and threatening him and his fiance after having followed them in unmarked vehicles. The arrests led to a protest through Milwaukee’s South Side last week.

Other residents also witnessed or filmed violent arrests, some of which involved parents violently dragged from their cars in front of their young children, who remain traumatized from the experiences, local advocates said. In those encounters, witnesses were unable to identify the agents. The targeted immigration arrest and eventual release earlier this year of Salah Sarsour, president of Milwaukee’s Islamic Society — which a federal judge ruled involved First Amendment retaliation against Sarsour by federal agencies — is also still fresh in the city’s memory. 

Milwaukee’s mask ordinance came out of meetings of the  Common Council and County Board of Supervisors last winter, as Wisconsinites watched on their phones, computers, and television sets the broad-daylight killings of Good and Pretti in Minnesota, as residents organized against the so-called Operation: Metro Surge. Agents were found to have lied about the events surrounding a third, non-fatal shooting in Minnesota, Homeland Security officials admitted in February. Concern was high, town halls were filled with people worried about their communities and wanting elected officials to do something about it, even if it later got struck down in court, Ald. Alex Brower said at the time. 

It’s unclear how local officials will respond to the letter from the federal government. The city attorney’s office did not immediately respond to a request for comment. 

A report published earlier this year by the University of Wisconsin Law School’s State Democracy Research Initiative noted that “courts and commentators have long pondered and debated the question of when and how state and local governments can regulate federal officers.” Local efforts to prevent agents from wearing masks “highlight unanswered questions in the Supremacy Clause and Intergovernmental Immunity doctrines,” the report states. “How should courts determine what actions are ‘authorized’ by federal law? When is something necessary and proper to the fulfillment of federal duties? Where is the line between state-laws that incidentally burden the federal government and those that directly regulate it? These are the questions that will be sorted out in court. While existing doctrine gives opponents of these laws ample grounds to challenge them, it also offers proponents a variety of cogent defenses.”

A spokesperson for Johnson said in an email that the mayor maintains that “some actions and behavior of Federal immigration agents have been inappropriate and dangerous.” The spokesperson added, “Federal agents are undermining the trust our residents have with their aggressive enforcement efforts.”