 He is said to have first worked for the drug traffickers Pedro Avilés Pérez and Ernesto Fonseca Carrillo before forming the Guadalajara Cartel with Miguel Ángel Félix Gallardo, Juan José Esparragoza Moreno, and others in the late 1970s.He has been cited as a pioneer of the drug trade in Mexico and has been described as one of the preeminent drug traffickers of his generation.Caro Quintero has been accused of ordering the abduction, torture, and murder of writer John Clay Walker and dentistry student Albert Radelat on January 30, 1985.