United Auto Workers President Shawn Fain retaliated against one of his own top lieutenants and said he would “slit” the throats of opposition within the union, according to a report by a court-appointed monitor assigned to watch the union’s governance after years of corruption.

Fain, a bombastic leader who railed against how automakers treated their workers during a 2023 strike, wrongly stripped duties from the union’s Treasury-Secretary Margaret Mock after she refused to approve certain expenses, according to the latest report by the monitor, Neil Barofsky, an attorney with Jenner & Block.

The report said that Fain had worked with members of his staff to remove Mock from roles that included oversight of financial approvals as “a consequence of her refusal to grant exceptions” to union spending rules, “including to those within Fain’s inner circle.”

UAW spokesman Jonah Furman did not return a call and a text message seeking comment. Feldman Strategies, a firm hired by the UAW to handle media relations, also declined comment.

The probe holds significance for how the union is governed. Fain, Mock and other ranking officers were elected in a direct vote by union members for the first time in the UAW’s 90-year history, instead of the previous system in which delegates selected officers. That move, created as part of a union’s settlement with the U.S. Department of Justice, set the stage to create a UAW board that isn’t composed of a single slate of nominees.

Barofsky’s report paints a picture of Fain as a profane leader who levied threats against those who disagreed with him. In a 2023 meeting, Fain said that he would “slit” or “cut” the “f—ing throats” of anyone who “messed” with certain members of his core team, the report said.

Fain later said the comment was intended to be a “lighthearted remark” to express loyalty to his staff, though attendees of the meeting did not interpret it as “humorous or rhetorical,” according to the report.

Barofsky’s oversight of the UAW’s compliance and governance practices stems from a lengthy corruption scandal involving misuse of union funds that sent two past presidents to prison. The expenses in the latest dispute are mostly related to union business, unlike past instances of leaders spending members’ dues on golf clubs, luxury lodgings and expensive dinners.

Barofsky’s report investigated allegations by Fain that Mock used her role as treasurer to thwart union business in a political play to get other board members to vote in agreement with her on union matters. The report said allegations of wrongdoing against Mock were “substantially unfounded” and that she should have her treasury duties reinstated.

The union’s board had prepared a report on Mock’s performance and discussed it at a meeting in February 2024. That report said Fain asked board directors LaShawn English and Laura Dickerson, both Black women, to bring up the complaints against Mock, who is also Black. Dickerson raised it and English seconded the motion.

Barofsky’s report says Fain later explained that he asked Dickerson to raise it because, “I thought it would be better coming from [Dickerson] than me, a white guy.”

On June 18, the 11 members who voted to remove Mock from her treasurer duties issued a statement after Barofsky’s report was filed standing behind their decision. The directors said that Mock’s handling of her job delayed organizing activities, which is a top priority for the UAW under Fain.

”Nearly three years into her term, she has failed to produce a budget or membership list. She has harmed our membership by obstructing critical bargaining and organizing activities,” the statement said. “She is under investigation by the Monitor for a significant compliance failure regarding our union’s investments.”

Barofsky’s report also probed counterclaims by Mock that Fain removed her from duties in a retaliatory move. 

In a statement, Mock said “the actions taken against me were disrespectful not only towards me as a UAW member and trade unionist, but to all of the members who voted for me as UAW Secretary-Treasurer.”

Barofsky said he is also looking into claims that Fain stripped another union officer of duties, but hasn’t reached a conclusion because the UAW has been slow to hand over documents the monitor has requested.