F.B.I. agents arrested a Milwaukee county judge on Friday on charges of obstructing immigration agents, saying she steered an undocumented immigrant through a side door in her courtroom while the agents waited to arrest him in a public hallway.
The charges against a sitting state court judge are a major escalation in the Trump administration’s battle with local authorities over deportations. The administration has demanded, under threat of investigation or prosecution, that local officials not impede federal efforts to deport millions of undocumented immigrants.
And the arrest of Judge Hannah Dugan comes after months of rising tensions between the Trump administration and the judiciary, in which the president and his top advisers have repeatedly assailed “local judges” for halting or questioning actions taken by the administration, particularly when it comes to immigration cases.
Charging documents described a confrontation last Friday at Judge Dugan’s courthouse, in which federal agents said she was “visibly upset and had a confrontational, angry demeanor” when a group of immigration, D.E.A. and F.B.I. agents came to arrest Eduardo Flores-Ruiz, a citizen of Mexico who was in her courtroom to face domestic violence charges.
According to the criminal complaint, the judge confronted the agents and told them to talk to the chief judge of the courthouse. She then returned to her courtroom.
“Despite having been advised of the administrative warrant for the arrest of Flores-Ruiz, Judge Dugan then escorted Flores-Ruiz and his counsel out of the courtroom through the ‘jury door,’ which leads to a nonpublic area of the courthouse,” said the complaint, which was written by an F.B.I. agent.
A Drug Enforcement Administration agent spotted Mr. Flores-Ruiz leaving the building and notified his colleagues, according to the complaint. Agents approached him on the street outside the courthouse. “A foot chase ensued,” the complaint said. “The agents pursued Flores-Ruiz for the entire length of the courthouse” before catching and arresting him, the complaint said.
The judge was charged with obstructing a proceeding of a federal agency and concealing an individual to prevent his discovery and arrest.
After a brief appearance as a defendant in federal court in Milwaukee, about a mile from her own courthouse, the judge was released on her own recognizance.
The bureau arrested Judge Dugan on suspicion that she “intentionally misdirected federal agents,” F.B.I. Director Kash Patel wrote on social media on Friday, before the charges were unsealed.
David Crowley, the Milwaukee County executive, criticized the F.B.I.’s handling of the case.
“It is clear that the F.B.I. is politicizing this situation to make an example of her and others across the country who oppose their attack on the judicial system and our nation’s immigration laws,” he said in a statement.
Attorney General Pam Bondi defended the arrest of the judge, telling Fox News that when someone obstructs justice by “escorting a criminal defendant out a back door, it will not be tolerated.”
“It doesn’t matter who you are, you’re going to be prosecuted,” Ms. Bondi said.
Ms. Bondi also discussed the recent arrest of a former judge in New Mexico who was charged with obstruction over harboring someone federal agents say was a Venezuelan gang member.
“Some of these judges think they’re above the law. They are not,” she said. “We will come after you and prosecute you. We will find you.”
Christopher A. Wellborn, the president of the National Association of Criminal Defense Lawyers, reacted with alarm to the judge’s arrest, saying American democracy “rests upon the independence of the judiciary.”
“Retaliatory action from the executive branch that appears to undermine this foundation demands our unwavering scrutiny and a resounding response,” he added.
The chief judge in Milwaukee County, Carl Ashley, said in a statement that Judge Dugan’s caseload would be handled by another jurist in the courthouse and declined to comment further.
The Trump administration has vowed to investigate and prosecute local officials who do not assist federal immigration enforcement efforts, denouncing what they call “sanctuary cities” for not doing more to assist federal apprehensions and deportations of millions of undocumented immigrants.
At the Justice Department, senior officials have urged prosecutors to look for cases in which local authorities, whether they are municipal, state or court officials, have tried to stop or hinder immigration agents.
The Milwaukee case involves a frequent flashpoint in that debate, when immigration agents try to arrest immigrants who are appearing in state court. Local authorities often chafe at such efforts, arguing they endanger public safety if people dealing with relatively minor legal issues feel it is unsafe to enter courthouses.
The charging papers against Judge Dugan suggested she was incensed to learn immigration agents were in the courthouse, and she called it “absurd,” according to one witness.
At first, the judge asked the immigration agent if he was in the courthouse for a hearing, and when the agent said no, the judge “stated that the agent ‘would need to leave the courthouse,’” according to the complaint.
Judge Dugan then asked the agent if they had a judicial warrant, to which the agent replied no, it was an administrative warrant, according to the complaint. I.C.E. typically uses administrative warrants, which are issued by the agency to apprehend people.
Such warrants do not carry the same authority as a warrant issued by a judge, meaning people in their homes typically don’t need to open their doors to immigration agents with only an administrative warrant.
In the first Trump administration, a local Massachusetts judge was indicted by the Justice Department on charges of obstructing immigration authorities. The charges were dropped after the judge agreed to refer herself to potential judicial discipline.
That case also involved allegations that a judge allowed a defendant being sought by I.C.E. agents to leave the building via a back door in order to avoid detention. The Massachusetts Judicial Conduct Commission has filed formal disciplinary charges against Judge Shelley Joseph. She has denied wrongdoing.
Glenn Thrush, Julie Bosman and Chris Cameron contributed reporting.