Robert George Irwin (August 5 1907 – 1975), was an American artist, sculptor, and recurring mental hospital patient who pleaded guilty to killing three people on Easter weekend in 1937 in the Beekman Hill area of New York City's Turtle Bay neighborhood. Irwin's prosecution, which ended through a plea-bargain that kept him incarcerated for life, renewed debate about the use and scope of New York's version of the insanity defense. Once sentenced, Irwin was deemed "definitely insane" by state psychiatrists. He spent the rest of his life in secure mental institutions.