California's attorney general has told a federal judge it's possible the state's largest power utility, Pacific Gas & Electric Co., could face charges up to murder if investigators find reckless operation of power equipment caused any deadly wildfires in the past two years.

The Sacramento Bee reports the brief is purely advisory, and any criminal charges would most likely be filed by county district attorneys, not the state.

The opinion was submitted to a judge overseeing a criminal case involving a PG&E natural gas pipeline explosion that killed eight people in the San Francisco suburb of San Bruno in 2010.

PG&E was convicted of violating federal pipeline safety laws, and the judge asked for the attorney general's opinion on whether any wildfires constitute a probation violation.

The company has until Monday to file its response.