Barnett Abba Slepian was an American physician and abortion provider who was assassinated in his home by James Charles Kopp, a militant member of the US anti-abortion movement.

James Charles Kopp is an American who was convicted in 2003 for the 1998 sniper-style murder of Barnett Slepian, an American physician from Amherst, New York who performed abortions. Prior to his capture, Kopp was on the FBI's list of Ten Most Wanted Fugitives. On June 7, 1999, he had become the 455th fugitive placed on the list by the FBI. He was affiliated with the militant Roman Catholic anti-abortion group known as The Lambs of Christ.