Washington Commanders owner Dan Snyder conducted a "shadow investigation" into allegations that he oversaw a toxic workplace culture, according to a document released Wednesday by a Congressional committee.

The U.S. House of Representatives' Committee on Oversight and Reform issued a 29-page memo, supported by more than 600 pages of depositions, based on its eight-month investigation.

Among the findings, the report alleges Snyder attempted to discredit former employees who made accusations of workplace sexual harassment and also hired private investigators to intimidate witnesses.

Snyder, 57, declined an invitation to testify before the committee, saying he would be out of town for business.

Committee chair Carolyn Maloney (D-New York) said Wednesday that she will subpoena Snyder to appear.

"The NFL is unwilling or unable to hold Mr. Snyder accountable," Maloney said. "That is why I am announcing now my intent to issue a subpoena for Mr. Snyder for a deposition next week. The committee will not be deterred in its investigation into the Washington Commanders."

The NFL fined the Commanders $10 million in June 2021 following an investigation led by Beth Wilkinson. Snyder stepped away from day-to-day operations at that time.

NFL commissioner Roger Goodell testified for more than two hours before the committee on Wednesday.

U.S. Rep. Rashida Tlaib (D-Michigan) asked Goodell if the NFL planned to take further actions against Snyder.

"I don't have the authority to remove him, Congresswoman," Goodell said.

An owner can only be removed by a three-quarters majority vote (24 of 32) of fellow owners, although Goodell does have the authority to recommend a vote.

"It is clear to me that the workplace in Washington was unprofessional and unacceptable in numerous respects: bullying, widespread disrespect toward colleagues, use of demeaning language, public embarrassment, and harassment," Goodell said in his prepared opening remarks.

"... The workplace at the Commanders today bears no resemblance to the workplace that has been described to this committee."