Gallup was conducting a national survey the fateful Saturday in October 1973 when President Richard Nixon's acting attorney general, Robert Bork, carried out his order to fire Watergate special prosecutor Archibald Cox. Bork had been thrust into the role of attorney general following the successive resignations of the previous U.S. attorney general and his deputy over the same directive.
In the months before that weekend, roughly a quarter of Americans thought Nixon should be "impeached and compelled to leave the presidency" over the mounting Watergate scandal. That figure rose to 33% in the Oct. 19-22 poll spanning Cox's firing on Oct. 20.
The immediate impact of that weekend's events may have been even greater than the overall poll numbers suggest. In reporting on the survey, George Gallup pointed out that support for Nixon's impeachment spiked midpoll, after Cox's firing:
"Interviewing taken before dismissal [Oct. 19-20] showed three in 10 in favor of compelling Nixon to leave office, while interviewing conducted afterwards [Oct. 21-22] showed the figure climbing to more than four in 10 (45%)."
A follow-up survey conducted later that month found support for impeachment dropping to 28%, which Gallup attributed to Nixon's Oct. 26 press conference and the announcement that he would release the White House tapes, as well as a recent diplomatic achievement with Russia.
However, by the next poll in early November, the percentage favoring impeachment was at a new high of 38%, and it remained at 35% or higher for as long as Gallup asked this question, through May 1974.
About this time, Gallup transitioned to a different measure of public support for impeachment -- asking Americans separately about bringing Nixon to trial in the Senate and removing him from office. As early as April 1974, a majority favored a Senate trial, and by the start of August, a majority favored his removal.
Nixon won the battle within his White House to remove Cox, thus preventing the investigator from obtaining audiotapes that would ultimately implicate him in a cover-up of the Watergate break-in. But the event, which came to be known as the Saturday Night Massacre, resulted in more Americans believing he should be impeached.
Nixon resigned on Aug. 8, 1974.
View the original 1973 Gallup news release on mounting public support for Nixon's impeachment.
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