Carlos Montenegro’s prison death leaves crucial questions unanswered

Montenegro died after the October 26, 2026, attack at California State Prison, Sacramento, in Folsom. Justin Castro, 47, and Luis Mendoza, 33, have been placed in restricted housing while the death is investigated as a homicide. That placement is an investigative measure, not a finding of criminal guilt. No charging decision has been established in the material available for this report.⁠2

The detailed account comes from the California Department of Corrections and Rehabilitation’s October 27 release. CBS Bay Area also reported the death, citing prison officials; its account does not independently establish how the confrontation unfolded. The distinction matters because the institution responsible for Montenegro’s custody is also the source of the public account of his final emergency.⁠1⁠2

At 6:43 p.m., correctional staff saw Castro and Mendoza attacking Montenegro on the upper tier of a housing unit, according to CDCR. Officers first ordered the prisoners to “get down.” When those orders were ignored, officers used five less-lethal, 40-millimeter direct-impact rounds to stop the attack.⁠2

Staff called 911 and began life-saving measures while moving Montenegro to the prison’s treatment and triage area. Paramedics arrived at the institution and pronounced him dead at 7:24 p.m.—41 minutes after staff first observed the attack. The earlier timestamp is not the time he was pronounced dead. Nor does the release establish how long the attack had been underway before officers saw it.⁠2

That interval describes the span between two reported events. It does not, by itself, establish a delay in treatment or explain why efforts to save Montenegro failed. The release says staff responded immediately, but it does not give a minute-by-minute medical chronology or describe his injuries.⁠2

The two improvised weapons recovered at the scene are important physical evidence, but their presence is not a complete account of the killing. Officials have not identified who used which weapon, described their construction or released a medical cause of death. They also have not said who was struck by the officers’ rounds. Calling the ammunition less lethal does not establish whether it caused injuries in this incident; no such finding has been released in the available material.⁠2

Investigators therefore have two tasks that should not be collapsed into one: reconstructing the attack and establishing the injuries that caused Montenegro’s death. The official allegation that staff witnessed two men attacking him is consequential. It still leaves each man’s actions, the role of the weapons and the medical evidence to be worked through.

Montenegro entered state custody from Los Angeles County on September 3, 2024. He was serving six years for assault with a deadly weapon, a second-strike offense. His sentence explains why he was incarcerated; it does not diminish the significance of his death inside the institution responsible for holding him.⁠2

Castro entered state custody from Los Angeles County on May 8, 2024. He was serving a third-strike sentence of life with the possibility of parole for attempted second-degree murder, first-degree burglary, second-degree robbery, kidnapping and carjacking, with a firearm-use enhancement.⁠2

Mendoza entered state custody from Orange County on March 15, 2017. His sentence was life with the possibility of parole for attempted second-degree murder, second-degree robbery, assault with a semiautomatic firearm and criminal gang activity. It included enhancements for firearm use and street gang acts committed during a serious felony. Those are existing convictions, not charges arising from Montenegro’s death. Mendoza’s gang-related conviction also does not establish a gang motive for this attack.⁠2

The prison is widely known as New Folsom Prison and stands next door to Folsom State Prison, a separate institution. Opened in 1986, California State Prison, Sacramento houses more than 2,200 people across medium, maximum and high security levels. CDCR reports approximately 1,500 employees institution-wide. Those totals do not reveal how many officers were on the affected tier or establish whether staffing or capacity played any role in the attack.⁠1⁠2

The prison’s Investigative Services Unit and the Sacramento County District Attorney’s Office are investigating. The Office of the Inspector General has been notified; that notification is not a completed oversight finding or confirmation of a separate investigation.⁠2

The next consequential development would be a supported account of the fatal injuries, a clearer reconstruction of each man’s conduct or a prosecutorial decision. For now, the record establishes a death in state custody and an official response—not a completed explanation of how the attack became fatal, and not a verdict against Castro or Mendoza.