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A Utah woman alleges in a lawsuit filed Wednesday that a longtime federal judge sexually assaulted her when he was a prosecutor and she was a teenage witness in a high-profile case 35 years ago.

Lawyers for Richard W. Roberts acknowledged an intimate relationship, but they called the accusations "categorically false" and said Roberts will challenge them in court.

The lawsuit was filed the same day Roberts announced his retirement as chief judge for the U.S. District Court for the District of Columbia, according to documents obtained by The National Law Journal. In a letter to the White House, Roberts said his retirement was effective Wednesday, based on medical advice for an unspecified disability.

The Utah Attorney General's Office announced after the lawsuit was filed that they have investigated the woman's allegations, but opted not to prosecute Roberts. Investigators found evidence of a sexual relationship, but they determined Roberts didn't break any laws, in part because the woman was old enough to consent to sexual relations under Utah laws in 1981.

Investigators did not interview Roberts about the allegations.

A lawyer for Terry Mitchell, now 51, says in the court filing that Roberts sexually abused her multiple times throughout the trial of white supremacist Joseph Paul Franklin, who killed two black joggers in Salt Lake City in 1980. Mitchell was with them and was wounded by shrapnel in the attack.

The Associated Press does not typically name people who say they were sexually assaulted, but Mitchell said she wants to make the allegations public. She told The Associated Press that she's coming forward because the allegations have been kept secret for too long.

Roberts could not be reached for comment, but Washington, D.C.-based lawyers with the firm Steptoe & Johnson said their client and Mitchell have stayed in touch since the trial.

"Roberts acknowledges that the relationship was indeed a bad lapse in judgment. However, the relationship did not occur until after the trial and had no bearing on the outcome of that trial," the law firm said in a statement.

Findings from the Utah attorney general's investigation were sent to several congressional committees. Rep. Jason Chaffetz, R-Utah, said the House Oversight and Government Reform Committee that he chairs has looked at the documentation. "Our initial review of the allegations has caused alarm and distress over their serious nature," Chaffetz said.

The abuse began after Roberts arranged for Mitchell to meet with him about the case in person, then took her to dinner and lured her into his hotel room, according to the lawsuit.

The lawsuit says he had sex with her that night, even though she said she was not ready for it, and that he continued to abuse her over the next several weeks before and during the trial.

Mitchell says she suppressed the memories of what happened shortly after, and only began to recall them in late 2013, when Roberts sent her two emails after Franklin's execution for another killing in Missouri, according to court documents.

The Utah attorney general's office started investigating in the summer of 2014 when an attorney representing Mitchell brought it

to their attention.
She was vulnerable from the shooting and other sexual assaults in her past when she met Roberts, and he exploited and coerced her, her attorney said.

The lawsuit says Roberts kept her quiet about the abuse by telling her multiple times before and after the trial that if anyone found out they had sex Franklin might not be convicted.

Utah prosecutors chose not to bring criminal charges based on the recommendation of Paul Cassell, a law professor and former federal judge who reviewed the findings.

The attorney general's office released a copy of Cassell's report on Wednesday. He wrote that then 16-year-old Mitchell was considered old enough under state laws at the time to consent to sex and the allegations she was coerced weren't strong enough to file charges.

Cassell concluded that Roberts may not have committed a crime but that he appears to have acted unethically and likely violated U.S. Department of Justice rules for attorney conduct, among other rule violations.