Solved case
Assassination of Luis Donaldo Colosio
Luis Donaldo Colosio, the PRI's presidential candidate, was shot in the head at a campaign rally in Tijuana on 23 March 1994 and died shortly after; Mario Aburto Martínez was arrested at the scene and convicted, though contradictory accounts and conspiracy theories persist.

Background
Luis Donaldo Colosio Murrieta (10 February 1950 – 23 March 1994) was a Mexican politician and economist who served in several senior roles within the Institutional Revolutionary Party (PRI), including as a federal deputy, senator for Sonora, chairman of the PRI's National Executive Committee, and Social Development Secretary under President Carlos Salinas de Gortari. In 1993, he was selected as the PRI's presidential candidate for the 1994 election (Source 1).
On 6 March 1994, Colosio delivered a speech in Mexico City, in front of the Monument to the Mexican Revolution, addressing indigenous communities, government abuse, and independence from government influence — remarks widely considered to mark a break with President Salinas. Speculation had circulated that former foreign secretary Manuel Camacho might replace Colosio as the PRI's candidate; Camacho announced he would not run, and Colosio was killed the following day (Source 1).
The Assassination
At approximately 5:05 pm local time on 23 March 1994, at a campaign rally in Lomas Taurinas, a low-income neighborhood of Tijuana, Baja California, Colosio was shot in the head with a .38 Special revolver that had originally been purchased in San Francisco. He collapsed at the scene; plans to fly him to a hospital in the United States were canceled, and he was instead taken to Tijuana's main hospital, where his death was announced hours later. Eyewitness accounts of the shooting have remained contradictory. Colosio received three bullet wounds, and it was never conclusively established whether all shots came from a single shooter (Source 1).
Mario Aburto Martínez was arrested at the scene and consistently maintained that he had acted alone. Authorities were criticized for showering, shaving, and giving Aburto a prison haircut before presenting him to media, fueling public doubts about whether the man shown was the same person arrested. The case was formally closed after multiple prosecutors handled the investigation, though controversy over its conduct has continued. Aburto has been held at the La Palma high-security facility in Almoloya de Juárez (Source 1).
Aftermath and Theories
Conspiracy theories about the assassination include claims of involvement by narcotraffickers and, most prominently among the Mexican public, a theory that Colosio was betrayed by figures within his own party, possibly including President Salinas, given the political tensions following Colosio's March 6 speech. Salinas publicly called the killing an "act of infamy." On 18 November 1994, Colosio's widow, Diana Laura Riojas, died of what was officially reported as pancreatic cancer while she had been investigating her husband's murder (Source 1).
The vacancy in the PRI candidacy led to the selection of Ernesto Zedillo, Colosio's former campaign manager, who went on to be elected president. Months later, PRI president José Francisco Ruiz Massieu, Salinas's brother-in-law, was also murdered. Colosio's father published a book in 2004 examining the case before his death in 2010. In 2021, Colosio's son publicly stated he forgave "the cowards" responsible for his father's death (Source 1).
Key facts
- Victims
- Luis Donaldo Colosio Murrieta
- Date
- 1990s
- Location
- Lomas Taurinas, Tijuana, Baja California, Mexico
- Case status
- solved
Case timeline
1950-02-10
Luis Donaldo Colosio Murrieta born in Magdalena de Kino, Sonora, Mexico.
1994-03-06
Colosio delivers a speech at the Monument to the Mexican Revolution in Mexico City widely seen as breaking with President Salinas.
1994-03-23
Colosio is shot in the head at a campaign rally in Lomas Taurinas, Tijuana, at approximately 5:05 pm; he dies hours later. Mario Aburto Martínez is arrested at the scene.
1994-11-18
Colosio's widow, Diana Laura Riojas, dies; officially attributed to pancreatic cancer.
2004-01-01
Colosio's father publishes a book examining the case.
2010-01-01
Colosio's father dies.
2021-02-11
Colosio's son, Luis Donaldo Colosio Riojas, visits Lomas Taurinas and publicly states he forgives those responsible for his father's death.
Best coverage
No coverage has been attached to this file yet.
People
Mario Aburto Martínez
CONVICTEDArrested at the scene of the shooting and held responsible; maintained he acted alone; remains imprisoned at the La Palma high-security facility.
Luis Donaldo Colosio Murrieta
VICTIMPRI presidential candidate shot and killed at a campaign rally in Tijuana on 23 March 1994.
Roles reflect public records and court outcomes at the time of writing — supporting citations are on file under Sources.
Archival records

portrait victim
Luis Donaldo Colosio
Credit: Via Wikipedia (non-free use rationale on file) · Copyrighted — editorial use · Source

archival location
Luis Donaldo Colosio Los Pinos Mexico 2018
Credit: Drkgk · CC0 · Source

archival location
MONUMENTO A LUIS DONALDO COLOSIO MURRIETA
Credit: JEDIKNIGHT1970 · CC BY 2.5 · Source
archival location
Monumento Luis Donaldo Colosio 3
Credit: Metamario · CC BY-SA 4.0 · Source
archival location
Monumento Luis Donaldo Colosio 2
Credit: Metamario · CC BY-SA 4.0 · Source
archival location
Monumento Luis Donaldo Colosio 1
Credit: Metamario · CC BY-SA 4.0 · Source

archival location
Luis Donaldo
Credit: Rajishev · CC BY-SA 3.0 · Source

other document
Libro de actas Aburto
Credit: PGR · Public domain · Source
Places
Common questions
- What happened to the victim?
- Luis Donaldo Colosio, the PRI's presidential candidate, was shot in the head at a campaign rally in Tijuana on 23 March 1994 and died shortly after; Mario Aburto Martínez was arrested at the scene and convicted, though contradictory accounts and conspiracy theories persist.
- Where did the crime happen?
- Lomas Taurinas, Tijuana, Baja California, Mexico.
- Who was convicted?
- Mario Aburto Martínez (Arrested at the scene of the shooting and held responsible; maintained he acted alone; remains imprisoned at the La Palma high-security facility.).
- What is the current status of the case?
- Status: solved. Last verified July 2026.
Sources
- ENCYCLOPEDICLuis Donaldo Colosio MurrietaWikipedia · 2026-07-05
- PRESSContemporaneous coverage — The New York TimesThe New York Times · 2026-07-05
- PRESSContemporaneous coverage — The Washington PostThe Washington Post · 2026-07-05
Record history
- First published
- JUL 05, 2026
- Last verified against sources
- JUL 05, 2026
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