Insane Clown Posse. Insane Clown Posse (ICP) is an American hip hop duo composed of Violent J (Joseph Bruce) and Shaggy 2 Dope (originally 2 Dope; Joseph Utsler). Founded in Detroit in 1989, Insane Clown Posse performs a style of hardcore hip hop known as horrorcore and is known for its elaborate live performances.