Thomas P. Corbett, also known as the "Glory to God man" who shot John Wilkes Booth.
By the way, as the question comes today, yesterday Lee Harvey Oswald was shot before being convicted, too. Why is it that nobody wants them to talk in a court?
Edit - Your answer is correct.
Not sure why you said Oswald was shot "yesterday," but that isn't really a topic for discussion here on the trivia game.
When Boston Corbett shot Booth, he did so against orders. The orders were for Booth to be taken alive, so apparently it is not true that nobody wanted him to talk in a court.
Hoosier