MILWAUKEE (CBS 58) — The U.S. Department of Justice has filed a lawsuit against the City of Milwaukee, Mayor Cavalier Johnson, City Attorney Evan Goyke and Police Chief Jeffrey Norman, challenging the city's ordinance that prohibits federal law enforcement officers from wearing masks and requires them to display individual identification while operating in Milwaukee.

The lawsuit, filed Thursday, argues the ordinance is an unconstitutional attempt by the city to regulate the federal government and interferes with federal law enforcement operations.

The DOJ also contends the law puts federal officers at greater risk by preventing them from concealing their identities.

"State and local leaders cannot tell Federal officers how to do their job," Associate Attorney General Stanley E. Woodward Jr. said. "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."

Assistant Attorney General Brett A. Shumate said Milwaukee's ordinance threatens both officers and public safety.

"Milwaukee's direct regulation of federal law enforcement operations threatens severe consequences for officers and public safety alike," Shumate said. "The Federal Government, not the city, gets to decide which equipment federal agents may or may not wear when performing their official duties."

First Assistant U.S. Attorney Brad Schimel also criticized the ordinance, calling it unconstitutional.

"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 lawsuit comes less than a week after Goyke announced Milwaukee intends to enforce the ordinance against federal law enforcement officers.

In a five-page letter sent to the DOJ on July 17, Goyke rejected the department's request to exempt federal agents from the city's mask ban and said Milwaukee would prosecute officers who are properly cited for violating the ordinance.

The DOJ previously argued the ordinance endangers federal officers by exposing them to "increasingly common threats of targeted harassment, tracking, interference, and assaults."

Milwaukee officials have countered that the ordinance is intended to promote transparency and accountability as federal immigration enforcement activity has increased in the city.

In his letter, Goyke wrote, "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."

The city also argued that because federal policy leaves masking and identification to the discretion of individual officers, the federal government has not demonstrated masks are essential to immigration enforcement.

"If masking and identity concealment are essential, why would the federal government leave this up to the discretion of the individual officer?" Goyke wrote.

The dispute has drawn support from immigration advocacy group Forward Latino, which has publicly backed Milwaukee's position, arguing the ordinance strengthens public trust by ensuring law enforcement officers remain identifiable.

The lawsuit now sets the stage for a legal battle over whether Milwaukee can enforce the ordinance against federal officers operating within city limits.