PRI Candidate Luis Donaldo Colosio Assassinated in Tijuana

Luis Donaldo Colosio, the PRI's presidential candidate for 1994 and widely seen as a reformer who might democratize the party, was shot twice at close range during a campaign rally in Tijuana's Lomas Taurinas neighborhood on March 23, 1994. Mario Aburto Martínez was arrested at the scene and later convicted as the lone gunman. Multiple independent forensic analyses suggested a second shooter; no conspiracy was ever officially proven. Colosio's death — on top of the EZLN uprising — shocked Mexico and defined 1994 as the country's most turbulent year since the Revolution.