CNN  —  House Oversight Chair James Comer has subpoenaed former President Joe Biden’s White House physician to appear for a deposition later this month, according to a copy of the subpoena letter shared with CNN. The subpoena to Dr. Kevin O’Connor marks an escalation of the Republican chairman’s probe into Biden’s mental fitness and decline. In the subpoena letter, Comer said O’Connor was not complying with the committee’s initial voluntary request for a transcribed interview. The letter from