Mark James Robert Essex (August 12, 1949 – January 7, 1973) was an American serial sniper and black nationalist who killed a total of nine people, including five policemen, and wounded 13 others in New Orleans on December 31, 1972 and January 7, 1973. He was killed in the second armed confrontation. He was also a one-time member of a New York-based branch of the Black Panthers and allegedly sought to kill white people and police officers due to racism he claimed to have experienced while enlisted in the Navy as well as his increasingly extremist anti-police views following a violent clash between Baton Rouge police officers and student civil rights demonstrators, during which two black demonstrators were shot and killed.