Ms. Powell, a lawyer who promoted conspiracy theories about election fraud after Donald J. Trump’s 2020 defeat, now says she never represented him or his campaign.
Scott Hall, a Trump supporter who is among the 19 people charged in a racketeering case involving the former president, is the first defendant to plead guilty.
Sidney Powell followed Kenneth Chesebro in demanding a speedy trial, but neither defendant in the election interference case wanted to be tried with the other.