On July 25, 1998, Joe Luis Saenz allegedly shot and killed two rival gang members in Los Angeles. Less than two weeks later, on August 5, 1998, Saenz allegedly kidnapped, raped, and murdered his girlfriend. Saenz allegedly murdered a fourth victim in October of 2008 in Los Angeles County.

Saenz is believed to work for a Mexican drug cartel, and is known to travel between the United States and Mexico. He may have removed his tattoos with a laser. He has reportedly made previous statements indicating plans to kill a police officer upon his arrest. He is believed to always carry a weapon.