"The Tercentenary Incident" is a science fiction/mystery short story by American writer Isaac Asimov.
[1] It was first published in the August 1976 issue of Ellery Queen's Mystery Magazine, and reprinted in the collections The Bicentennial Man and Other Stories (1976) and The Complete Robot (1982).
The concept of a robot taking political office in the guise of a human was also the theme of Asimov's 1946 story, "Evidence".
The beginning of the story details the Tercentenary speech by the 57th president, Hugo Allen Winkler, who is described by Secret Service agent Lawrence Edwards as a "vote-grabber, a promiser" who has failed to get anything done during his first term in office.
The death of one man was acceptable to save three billion, and this is what allowed it to circumvent the First Law of Robotics.