The commission’s findings could jeopardize the probation the company was placed on after the 2010 gas pipeline explosion.

Judge William H. Alsup of Federal District Court ruled this year that PG&E had violated the probation, contending that the company had not adequately informed federal supervisors of a fire-related investigation by a state district attorney. Judge Alsup threatened to force PG&E to carry out a far-reaching and costly overhaul of its power lines, but ultimately scaled back his demands.

The judge could now revisit that decision in light of the new report. PG&E has acknowledged that it could be in violation of its probation if “reckless operation or maintenance” of its power lines was responsible for a wildfire and if the company was found to have violated federal, state or local laws.

A spokesman for PG&E said the company accepted the commission’s conclusion that its equipment had caused the Camp Fire. The utility said it had since stepped up safety efforts by, among other things, inspecting almost 730,000 transmission, distribution and substation structures and over 25 million electrical components.

“We remain deeply sorry about the role our equipment had in this tragedy, and we apologize to all those impacted by the devastating Camp Fire,” said Paul Doherty , the PG&E spokesman.

PG&E has been under increasing scrutiny since 2017, when its equipment was implicated in several devastating wildfires in Northern California.

The utility filed for bankruptcy protection in January after amassing tens of billions of dollars in liability for the damage caused by fires its equipment started in 2017 and 2018. This year, the utility angered customers after moving to cut off power to millions of Californians to prevent more wildfires.