The Eaton Fire that ripped through Altadena on January 7, 2025 now has an official cause, and it lands on a piece of equipment that had not carried power in more than 50 years.
Los Angeles County fire officials released their report on Tuesday, August 4, 2026, closing out an 18-month investigation into one of the deadliest fires in the region’s history. The finding is blunt. Electrical arcing on an out-of-service Southern California Edison transmission tower dropped burning material into dry brush below, and that brush went up during a brutal Santa Ana windstorm. Nineteen people died. More than 9,400 homes and businesses were destroyed or damaged.
For the thousands of families who lost everything, this is the answer they have been waiting a year and a half to hear. And it changes the fight over who pays for it.
A tower that hadn’t worked since Nixon was president
The strangest detail in this whole story is the age of the tower. According to a court filing from Edison itself, the transmission tower where the fire started had been idle since 1971. That is 54 years out of service by the time the fire broke out.
You would think a tower that stopped doing its job during the Nixon administration would be about as dangerous as a fence post. Investigators say that is not how it worked. Edison suggested in a February regulatory filing that the old tower or circuit might have picked up electricity through something called induction, basically a live line nearby passing energy over to the dead one without a direct connection. That would have been enough to create the arcing.
The point of origin was pinned to dry brush on a spur ridge directly beneath the SCE towers above Eaton Canyon. Investigators used the National Wildfire Coordinating Group’s standard method and brought in electrical and metallurgical experts to figure out exactly what happened up on that ridge.
Two flashes, seconds apart
The report describes what the video evidence showed in plain language. The investigation team found two electrical arcing events that happened in quick succession, and those events led to unknown burning material falling from the tower into the dry fuel bed below.
That video did not come out of nowhere. In the days and weeks after the fire, several clips surfaced that appeared to show the very first flames in Eaton Canyon near the utility infrastructure. One piece was cellphone video showing flames growing right under one of the towers. That footage became a core part of the case.
The county did not run this alone. The Los Angeles County Arson Fire Investigation Unit worked the case jointly with Cal Fire, the state’s forestry and fire protection agency. Two agencies, outside experts, video, and physical evidence all pointing at the same spot on the ridge.
The blue light a neighbor saw
Machines and metallurgy tell part of the story. The people who were standing there tell the rest. The report includes interviews with residents who watched the fire start, and their accounts line up with the science.
One witness who spotted flames under an electrical tower said he saw an arc while watching, and he described it as a blue light. He started snapping photos around 6:25 p.m., then watched the blaze spread fast as the wind whipped through the canyon. Other residents said the flames they saw came from below the power lines.
When the physical evidence, the video, and a neighbor describing a blue flash all say the same thing, the conclusion tends to write itself. That blue light is the kind of detail that turns a technical report into something you can actually picture.
How much the fire took
The numbers are hard to sit with. The fire killed 19 people and burned roughly 22 square miles. Some reports put the burn area at around 14,000 acres across the surrounding neighborhoods. More than 9,400 homes and businesses were destroyed or damaged.
It took firefighters nearly a month to shut it down. The fire started the night of January 7 and was not fully contained until 24 days later, after it pushed into Altadena, Pasadena, Sierra Madre, and La Canada Flintridge. The weather that night was about as bad as it gets for fire: high temperatures, low humidity, and powerful winds all stacked on top of each other.
Altadena took the worst of it. The middle-class neighborhood, full of longtime homeowners and families, was gutted. Of the 19 people who died, 18 lived in west Altadena. That single fact sits at the center of a separate argument that is still playing out in court.
Edison’s argument: the tower was too old to count
Here is where the legal fight gets interesting. California has a rule called strict liability for utilities. In plain terms, if a utility’s equipment starts a fire, the utility can be on the hook even if it did nothing careless. That rule is why fire victims often win against power companies.
Edison’s lawyers came up with a creative response. In a court filing last week, the company argued that because the tower had been decommissioned since 1971, it should not count as the kind of active public infrastructure that triggers the strict liability rule. Basically, the company is saying a dead tower is not the same as a working power line, so the special standard should not apply.
It is a clever legal move, but it runs headfirst into the county report. The official finding names that exact out-of-service tower as the source of the arcing that started everything. Edison wants to treat the tower as a harmless relic. The report treats it as the ignition point for a fire that killed 19 people.
More than 10,000 people are suing
Edison is not fighting a handful of lawsuits. The company faces suits from more than 10,000 plaintiffs who say its equipment started the fire. That is a wall of legal pressure, and the new report hands every one of those plaintiffs a government finding that backs up their case.
Edison has not been sitting quietly on the defensive, either. Earlier this year the utility filed its own claims arguing that Los Angeles County agencies failed to send timely evacuation warnings to residents in east and west Altadena. Remember that 18 of the 19 people who died lived in west Altadena. Edison’s position is that even if its equipment lit the spark, the death toll was made worse by slow warnings on the county’s side.
So you have a case where the fire company blames the utility for starting it, and the utility partly blames the county for how deadly it became. Both of those fights are far from over.
What Edison is saying now
The company’s public response has been measured. Kathleen Dunleavy, a spokesperson for Southern California Edison, said the utility received the report and is reviewing it. She added that Edison has taken its potential role in the start of the fire seriously from the very beginning.
Dunleavy also noted that Edison had already acknowledged it was likely the company’s equipment was associated with the ignition of the Eaton Fire, and she said the utility continues to support the community as it recovers. That is a notable gap between the public statements and the legal filings. In front of a microphone, Edison sounds cooperative. In front of a judge, its lawyers are arguing the tower was too old to trigger the liability rule.
Why parts of the report are blacked out
If you go looking for the full report, you will find sections that are redacted. The county said it blacked out parts for two reasons. First, the Los Angeles County District Attorney’s Office has an ongoing review of the evidence from this fire. Second, some material was hidden to protect the privacy of individuals.
The mention of a district attorney’s review is worth sitting with. It signals that officials are still looking at the evidence, and the county wants to keep its options open while that work continues. A civil case decides who pays. A DA’s review can go further.
For now, the biggest question left over from that terrible night has an answer. A steel tower that stopped carrying power more than half a century ago threw sparks into dry brush during a windstorm, and a whole neighborhood paid for it. The county has said as much in writing. The courts get to decide what that sentence is worth.
