Palisades fire suspect was angry about romantic relationship, researched Luigi Mangione, prosecutors say

LOS ANGELES - Federal prosecutors say the man suspected of starting the blaze that would eventually become the deadly Palisades fire was distraught over his relationship with a former co-worker, angry about not having plans on New Year's Eve and "pissed off about the world," according to new court filings.

Jonathan Rinderknecht, 30, was described by Uber passengers he drove as "angry, intense, driving erratically, and ranting about being ‘pissed off at the world'" prosecutors said in a trial memorandum, which outlines the evidence the government plans to present at trial. He is accused of setting the Lachman fire on Jan. 1, 2025, which authorities say became a holdover fire that turned into the Palisades fire.

He has pleaded not guilty to the three federal charges he faces, of destruction of property by means of fire, arson affecting property used in interstate commerce and timber set afire.

"If being a 29-year-old man alone on NY's Eve with plans that fell through was a motive for arson, I would gather we would have millions of arsonists amongst us. It is categorically a silly theory of motive," Rinderknecht's attorney, Steven Haney, said.

The government said in the court filing that on the night of New Year's Eve, Rinderknecht was upset about his relationship with a former co-worker, whom he had dated for a time in March 2024.. He had messaged her about plans for New Year's Eve during the week leading up to the holiday and she asked for space on Dec. 30, 2024, which Rinderknecht "viseral(ly) react(ed) to," leaving her two voicemails described as "manic" by prosecutors.

He tried to make plans with two other people unsuccessfully, leaving him alone on New Year's Eve, "frustrat(ed) about being unable to find companionship on New Year's Eve," according to the government.

According to court filings, Rinderknecht talked about accused UnitedHealthcare CEO shooter Luigi Mangione, capitalism and vigilantism with passengers on Dec. 31, 2024, and Jan. 1, 2025, when he is accused of starting a fire near Hidden Buddha Hill in the Pacific Palisades just after midnight.

Prosecutors say a DNA expert will testify during trial that the suspect's DNA was on a BIC lighter found in his car, a fire investigator will testify that the Palisades fire was a holdover fire from the Lachman fire and other experts will testify to their opinions that the Lachman fire was not caused by fireworks or power lines.

In previous filings and press statements, Rinderknecht's attorney has focused on what the defense calls a lack of evidence that Rinderknecht started the fire, his reporting of the fire and cooperation with authorities and fire authorities' failure to put out the Lachman fire, pointing to depositions of firefighters and state parks employees as evidence that the fire was abandoned by authorities. Haney argued "gross, unforeseeable negligence" and that authorities knew the fire was still smoldering and had hot spots, but did not utilize thermal imaging, pulled hoses and did not take precautionary measures to monitor the fire as Red Flag Warnings for winds were issued, according to court documents.

Rinderknecht, who was working as an Uber driver and living in North Hollywood at the time of the fire, had "happier times" living in the Palisades with an "ex-lover," who he also messaged the night of the fire, according to prosecutors. The ex did not respond, court filings state.

In an interview with investigators in late January 2025, when asked why someone might commit arson in the Palisades, prosecutors say Rinderknecht "responded that it would be out of resentment of the rich enjoying their money as ‘we're basically being enslaved by them,'" and likened the act to Mangione's alleged crime.

Rinderknecht searched for news about Mangione and searched "free Luigi Mangione," "lets take down all the billionaires," and "reddit lets kill all the billionaires," a few weeks before the Lachman fire, prosecutors said.

Prosecutors highlighted allegations of previous behavior of the suspect in the filings, including allegedly admiring the 2018 Woolsey fire, burning a Bible, threatening to burn his sister's house down and using ChatGPT to generate images of people running from a burning forest.

Rinderknecht used ChatGPT as "a confidant and diary," according to prosecutors, who referenced his use of the AI system in previous filings. He input his feelings about his former co-worker into ChatGPT, "expressing his extreme displeasure of her treatment of him" in some prompts, prosecutors said in a recent filing.

Rinderknecht's trial is expected to begin June 8. He faces up to 45 years in federal prison if convicted.

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This story was originally published May 1, 2026 at 10:03 PM.