A key cooperator in special counsel Robert Mueller's Russia investigation has begun testifying in the foreign lobbying trial of prominent Washington attorney Greg Craig.
Rick Gates was on the witness stand Thursday morning in Washington's federal court.
Gates is a former campaign aide to President Donald Trump who pleaded guilty last year in Mueller's investigation and agreed to cooperate with prosecutors in multiple probes.
One of those cases concerns Craig, a former White House counsel under President Barack Obama.
Craig was charged in April with willfully concealing material facts from the Justice Department about work he performed for the Ukrainian government that also involved Gates and then-business partner Paul Manafort.
Gates is acknowledging his past crimes on the witness stand, and that he is testifying under a cooperation agreement.