Did lightning cause the Greer Creek wildfire near Vanderhoof in 2010?

Or was it sparked by a logging contractor's feller buncher, which is a piece of heavy equipment?

That question has been at the centre of a lengthy legal fight between the B.C. government, Canfor Corporation, and one of its harvesting contractors, Barlow Lake Logging Ltd.

It goes to the heart of determining liability for the $5.5-million cost of suppressing the 6,100-hectare wildfire.

The blaze caused an evacuation of 30 homes and required the services of 60 firefighters, six helicopters, and two air tankers.

On Friday (April 6), two out of three B.C. Court of Appeal judges upheld the B.C. government's appeal of an earlier ruling. In 2016, B.C Supreme Court Justice Bruce Greyall dismissed the province's claim of negligence, ruling that lightning caused the fire. 

Appellate justices Daphne Smith and Justice Lauri Ann Fenlon ordered a new trial to hear the province's claim of negligence.

That's because they concluded that Greyall "did not address the issue of whether the respondents' breach of the standards of care by failing to conduct a fire watch until 5:00 p.m. caused the Province's loss".

The B.C. Court of Appeal's summary of the decision states that the "trial judge erroneously interpreted the words 'after work' to mean that the duties of the fire watcher commenced after the cessation of high risk activity. Properly interpreted, when the legislative scheme is read as a whole, 'after work' requires the duties of a fire watcher to begin after the completion of industrial activity at the site of high risk activity."

This interpretation extends the amount of time that a fire watcher must be monitoring a site. 

"In doing so, I would note that as the Province did not challenge on appeal the finding of the trial judge that the fire originated as a lightning-caused holdover fire, that finding is not open to be re-litigated in the new trial," wrote Smith in reasons that were supported by Fenlon. 

A third member of the B.C. Court of Appeal panel, Nicole Garson, wrote dissenting reasons dismissing the province's appeal concerning its claim of negligence.

She concluded that Greyall's interpretation of the fire-watch regulation was correct.

Greyall's earlier ruling noted that a feller buncher was near the Greer Creek fire when a spotter plane flew over the blaze.

"The parties agree the operation of a feller buncher constitutes a high risk activity and a potential cause of fire," the trial judge wrote in 2016.

Canfor's claimed at trial that the province "did not take sufficient action to suppress or extinguish" the fire.

That was dismissed in B.C. Supreme Court and dismissed again on Friday by all three judges on the B.C. Court of Appeal panel.