Bob Schieffer calls W.H. explanation of Comey's firing "amateur hour"
President Trump's firing of James Comey has been compared to the actions of our 37th president, Richard Nixon. CBS News contributor Bob Schieffer joins "CBS This Morning" from Washington to discuss the damage caused by the White House's inconsistent explanations of Comey's firing and the importance of Mr. Trump proving his campaign's alleged ties to Russia are false.