Not that I'm inclined to be sympathetic to his view, but I think I understand it. From his perspective whatever the investigation found is irrelevant because it was motivated for the wrong reasons. The idea being that he would not have been caught if he hadn't been outspoken on other issues.
It seems that to the radical left the one unforgivable sin is to expose the sin of others. Thus I'm sure that in his universe he is pursuing a courageous and righteous coarse of action.