Peter Hains

Peter Hains (born January 9, 1872) was an Army Captain convicted of killing his wife's lover. The case became a sensational murder trial in New York City in 1908.
Abetted by his brother, sea novelist Thornton Jenkins Hains, Peter Hains gunned down prominent magazine editor and Harper's contributor William Annis at the latter's yacht club in Bayside, Queens. The crime, known as the Hains-Annis Case or the "Murder at the Regatta," played an important role in the development of criminal and matrimonial law. Peter Hains was convicted of manslaughter and received an eight-year sentence, but later received a pardon from the governor of New York. His brother pleaded temporary insanity and was acquitted of manslaughter.
It was one of the last cases in which a defendant pleaded Dementia Americana, the psychiatric pathology that allegedly drove American men to kill the lovers of their unfaithful wives. Harry Thaw used a similar defense during his trial for the murder of architect Stanford White.
The trial was front page news across the country at the time and ranks with the trials of Josephine Terranova and Richard Bruno Hauptmann as among the most widely watched and reported American criminal trials of the first half of the twentieth century.