Three more North Bay families are expected to file a lawsuit against PG&E Thursday, implicating the utility in the devastating wildfires that destroyed thousands of homes in Napa, Sonoma, and Mendocino counties earlier this month — this despite the fact that the investigations into the fires' causes remain ongoing. But we're also learning this week that a legislator is calling out a specific device PG&E has in use to prevent blackouts as a potential cause that is in need of investigation — a device that utilities in Southern California routinely disable during fire season for the very reason that it can spark wildfires.

The new lawsuit, as NBC Bay Area reports, will join lawsuits already filed on behalf of twelve individuals impacted by the fires, and it accuses PG&E of "gross negligence" with regard to the maintenance of its power lines and equipment. We know from a recent audit that has come to light from the state's Public Utilities Commission that PG&E had multiple citations for maintenance issues in Sonoma County in recent years. And all these suits appear to be early efforts to extract damages from PG&E, assuming that they will be found liable when the fire investigations are complete.

Meanwhile, as the Chronicle reports, State Senator Jerry Hill (D-San Mateo), a perennial critic of PG&E ever since the 2010 San Bruno blast killed some of his constituents, is calling on investigators to focus on devices affixed to power line poles known as "reclosers," which send pulses of electricity into lines where service becomes briefly interrupted, helping to prevent blackouts and outages when lines are not actually damaged.

Hill points to a public hearing he held two years ago in which representatives from PG&E spoke alongside counterparts from California's other two utilities, San Diego Gas & Electric Co. and Southern California Edison. In that hearing the two Southern California companies said that they had a practice of blocking the reclosers from working during fire season, as the devices can be known to spark wildfires when a downed line is, for instance, in contact with a nearby tree or dry brush. At the time, PG&E defended its stance of not doing this because the reclosers improved reliability across the system, but the hearing appears to have led to a pilot program in which PG&E was experimenting with turning off some of the devices during fire season — and, in fact, per the Chron, some of the reclosers in the North Bay were part of this pilot program, but many were not.

"Frankly, not turning off the reclosers could have started many if not all of the fires,” Hill tells the Chronicle. He further says that he feels "misled" into believing that PG&E had begun using the same practice as their SoCal counterparts in shutting all the reclosers off.

We learned this week via a report PG&E filed with state regulators that in the wake of the fires, they found many instances of trees that had been blown over and knocked down power lines, despite in some cases being originally rooted as far as 50 feet away from the lines.

Earlier this week, four weeks after the fires began, the largest of the fires in Sonoma and Napa counties finally reached 100 percent containment.

All related coverage of the North Bay wildfires on SFist.