MANCHESTER, N.H. — President Trump has decided to hire the longtime Washington lawyer Joseph E. diGenova, who has pushed the theory on television that Mr. Trump was framed by F.B.I. and Justice Department officials, to bolster his legal team, according to three people told of the decision.
Mr. diGenova is not expected to take a lead role but will instead serve as a more aggressive player on the president’s legal team. Mr. Trump broke over the weekend from the longstanding advice of some of his lawyers that he refrain from directly attacking the special counsel, Robert S. Mueller III, a sign of his growing unease with the investigation.
The hire has not been announced, and Mr. Trump frequently changes his mind and sometimes adjusts his plans based on media coverage. It was not clear whether Mr. Trump planned to hire other lawyers.
Mr. diGenova has endorsed the notion that a secretive group of F.B.I. agents concocted the Russia investigation as a way to keep Mr. Trump from becoming president. “There was a brazen plot to illegally exonerate Hillary Clinton and, if she didn’t win the election, to then frame Donald Trump with a falsely created crime,” he said on Fox News in January. He added, “Make no mistake about it: A group of F.B.I. and D.O.J. people were trying to frame Donald Trump of a falsely created crime.”