Former U.S. attorney for the District of Columbia during the Reagan era, Joe diGenova, is leading a federal investigation into former federal officials who investigated President Donald Trump. The probe will reach back to a previous Justice Department inquiry into Russian interference in the 2016 presidential election. DiGenova's appointment comes after Maria Medetis Long, who was in charge of the investigation, objected to moving forward with an investigation into ex-CIA Director John Brennan after claims from Trump allies that he should be charged over false testimony. The grand conspiracy investigation could potentially tie all investigations into Trump into one massive criminal conspiracy, allowing for individuals to be charged based on past conduct within five years.