fbi officials had grown suspicious of mr. trump's ties to russia during the 2016 campaign but held off on opening investigation into him, the people said. in part because they were uncertain how to proceed with an inquiry of such sensitivity and magnitude. the president's activities before and after mr. comey's firing, may 2017, particularly two instances in which mr. trump tied the comey dismissal to the russia investigation helped prompt the counterintelligence aspect of the inquiry, the people said. and according to "the times," one of the instances was a letter that trump wrote with the help of senior aide, steven miller, before he fired comey laying out the underpinning reasons for doing so. "times" reported on that letter back in 2017 and notes that then white house counsel don mcgahn