The move is a significant expansion of the Justice Department’s investigation into the state’s leaders, including Gov. Tim Walz and Mayor Jacob Frey of Minneapolis.
Mayor Jacob Frey of Minneapolis at a news conference this month. The Trump administration’s investigation was initially said to have focused on him and Gov. Tim Walz of Minnesota.
For weeks, judges have pressed Ms. Halligan to explain why she continues to identify herself in court filings as the U.S. attorney, despite a ruling in November that she was unlawfully appointed to the job.
Judges took the extraordinary step of publicly appealing for applicants to replace Lindsey Halligan, whose short tumultuous tenure was marred by significant missteps in court.
As the F.B.I. has added payback to its portfolio, Republican lawmakers like Senator Charles E. Grassley have emerged as a clearinghouse for leaks and whistle-blowers.
Under Kash Patel, F.B.I. personnel have worked to paint a damning, one-sided narrative intended to discredit and embarrass federal law enforcement officials who investigated Donald J. Trump and his allies.
Jacob Frey, the mayor of Minneapolis, at a news conference this month. He and Gov. Tim Walz of Minnesota are being investigated by the Justice Department, according to a senior law enforcement official.
Global economic leaders have expressed concern about the credibility of the world’s most important economic institution after the Justice Department’s announcement of an investigation into the Federal Reserve chair, Jerome H. Powell.