Minnesota’s new U.S. attorney formally took office Monday.

Erica H. MacDonald began her tenure as the state’s top federal law enforcement official after being sworn in by the district’s chief federal judge. She assumes leadership of an office that had been without a presidentially appointed U.S. attorney since the March 2017 forced resignation of Andrew Luger and 45 other Obama administration holdovers nationwide.

MacDonald, who has served as a Dakota County district court judge since 2009, first applied for one of two federal judicial vacancies that opened in the past two years before President Donald Trump nominated her to be U.S. attorney in April.

She will lead a staff of 99 employees while returning to an office where she spent nearly a decade as an assistant U.S. attorney, including helping lead efforts against human trafficking and prosecuting cases in Indian Country.

“It is truly an honor to return to this office and serve as United States Attorney,” MacDonald said in a statement Monday. “I am looking forward to leading a team of dedicated professionals and working alongside our law enforcement partners in the pursuit of justice on behalf of all Minnesotans.”

MacDonald came to the Minnesota office after first working as a federal prosecutor in Illinois, where she began her legal career as a clerk for a federal judge in Chicago.

She succeeds Gregory Brooker, who took over the office on an acting basis last year. Attorney General Jeff Sessions and the district’s federal judges appointed him to continue as U.S. attorney until MacDonald could take the oath of office.