The federal trial begins Monday for a Wisconsin judge facing accusations of hiding an undocumented immigrant to shield him from arrest by immigration officials.

Milwaukee County Circuit Court Judge Hannah Dugan stands charged in a federal indictment with two counts. The indictment claims she interfered with Department of Homeland Security removal proceedings and deliberately concealed the man from immigration officers at a courthouse in April.

Judge Dugan has entered a plea of not guilty.

The trial, taking place in Milwaukee, will commence with opening statements on Monday, following the completion of jury selection last week.

The prosecution has indicated plans to call between 25 and 28 witnesses to testify during the proceedings.

If found guilty of the charges, Dugan could be sentenced to a maximum of six years in prison.

According to federal prosecutors, Dugan encountered federal agents who were at the Milwaukee County Circuit Court on April 18 to arrest Eduardo Flores-Ruiz, who was appearing in her courtroom on a battery charge.

Prosecutors say that after speaking to the agents, Dugan directed them to the chief judge’s office down the hall and then sent Flores-Ruiz and his attorney out a non-public door in an alleged attempt, authorities claim, to help him evade arrest on immigration violations.

Dugan’s lawyers have called her arrest “virtually unprecedented” and sought to dismiss the case, arguing she has judicial immunity for official acts and her prosecution is unconstitutional. Judge Lynn Adelman denied the motion, finding there was “no basis for granting immunity simply because some of the allegations in the indictment describe conduct that could be considered ‘part of a judge’s job.’”

The Wisconsin Supreme Court suspended Dugan in the wake of her arrest, stating in an order it was “in the public interest that she be temporarily relieved of her official duties.”

Flores-Ruiz, a native of Mexico, was later arrested and charged with unlawful reentry into the U.S.

He was sentenced to time served earlier this month after pleading guilty to the charge, federal court records show. DHS said last month he had been deported.