Actually, Trump confessed that he fired Comey because he was investigating him. Trump's actions were those of a guilty man. ha ha.
Trump: [A] lot of people say to me, 'How you survived is one of the most incredible things.' Don't forget, I fired Comey. Had I not fired Comey, you might not be talking to me right now about a beautiful book of four years at the White House. And we'll see about the future. The future's going to be very interesting. But I fired Comey, that whole group, and now that group is coming back again. I mean, it's not believable. It shouldn't be allowed to happen. It shouldn't be allowed to happen."