The Justice Department just gave the clearest sign yet that Mueller is homing in on Comey's firing [iInsert: The Department of Justice won’t allow the Senate Judiciary Committee to interview two top FBI officials, Carl Ghattas and James Rybicki, about the circumstances surrounding former FBI Director James Comey’s dismissal in May, according to a letter obtained by CNN. ] http://www.businessinsider.com/mueller-comey-firing-trump-letter-2017-9