United Auto Workers President Shawn Fain testifies about the toll of working hours on laborers before the Senate Health, Education, Labor and Pensions Committee in the Dirksen Senate Office Building on Capitol Hill in Washington, D.C., on March 14, 2024.

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DETROIT — United Auto Workers President Shawn Fain is under investigation by a federal court-appointed watchdog who is tasked with monitoring the union and eliminating corruption, according to a Monday court filing.

The monitor, Neil Barofsky, is investigating whether Fain abused his power as union president. He also accuses union leaders, including Fain, of obstructing the investigation and interfering with his access to information.

Such actions could potentially violate a 2020 consent decree between the UAW and the U.S. Department of Justice that avoided a federal takeover of the union.

“The Monitor has attempted for months to garner the Union’s cooperation in gathering the information needed to conduct a full investigation, but the Union has effectively slow-rolled the Monitor’s access to requested documents,” the court filing reads.

More recently, the filing says the monitor expanded the investigation to include additional allegations of retaliation by Fain against one of the union’s vice presidents.

The monitor also opened an unrelated investigation into another unnamed UAW International Executive Board, or IEB, member, a regional director, after receiving allegations of potential embezzlement, according to the filing.

The UAW did not immediately respond to CNBC’s request for comment.

United Auto Workers President Shawn Fain (right) and UAW Secretary-Treasurer Margaret Mock (left) lead a march outside Stellantis’ Ram 1500 plant in Sterling Heights, Michigan, after the union called a strike at the plant on Oct. 23, 2023.

Michael Wayland / CNBC

The union is in the middle of a national organizing drive of nonunion automakers. The accusations follow Fain’s rise to international prominence after the union under his leadership scored record-setting contracts last year with General Motors, Ford Motor and Stellantis.

The court filing, which was first reported by The Detroit News, says Barofsky’s concerns largely began in February, after the monitor “began investigating current members of the IEB—including the President, Secretary-Treasurer, and one of the Union’s Regional Directors.”

The probe stems from union leaders removing all responsibilities assigned to Secretary-Treasurer Margaret Mock that were not constitutionally required amid allegations she had engaged in misconduct while carrying out her financial oversight responsibilities.

In response, the filing says Mock “lodged allegations of her own against the Union’s President that, among other things, the charges against her were false, and that the removal of her authority was improperly instigated in retaliation for her refusal or reluctance to authorize certain expenditures.”

The filing states more than three months after the monitor’s initial document request, the union has produced “a very small portion (approximately 2,600 documents) of the current potentially relevant pool of approximately 116,000—and with more than 80% of those documents only produced on June 6, 2024, days before the issuance of this report.”

The monitor believes the “union’s delay of relevant documents is obstructing and interfering with his access to information needed for his investigative work, and, if left unaddressed, is an apparent violation of the Consent Decree,” the filing reads.

The consent decree followed a yearslong corruption probe into the union involving embezzlement, bribery and other charges. It resulted in several convictions of union leaders and Fiat Chrysler executives, including two past union presidents.

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