The Sept. 3-9 Gallup poll asked how Trump's ethical standards compare with those of seven of his eight predecessors. Trump fares worst in relation to Ronald Reagan, Jimmy Carter, George H.W. and George W. Bush, each of whom has a greater-than 2-to-1 advantage over Trump in perceptions of having higher vs. lower ethics. Barack Obama and Bill Clinton have smaller, but still sizable, advantages over Trump in the public's perceptions of their ethical standards. Nixon is the closest to being on par with Trump.
Nixon, who was charged with obstruction of justice, abuse of power, and contempt of Congress as a result of his involvement in the Watergate scandal, is the only U.S. president to resign from office, which he did in 1974, before his expected impeachment. Clinton was impeached in 1998 on the grounds of perjury and obstruction of justice stemming from his extramarital affair with White House intern Monica Lewinsky, but he was acquitted when his case went to trial in the Senate.