Australia's highest court has dismissed an appeal by Western Power over its duty of care in relation to a bushfire sparked by a fallen power pole.
The 2014 Parkerville blaze in the Perth Hills destroyed 57 homes, partially damaged six homes and burnt 392 hectares.
The termite-ridden jarrah pole was privately owned by pensioner Noreen Campbell but connected to infrastructure owned by the state-run utility and serviced by its subcontractor Thiess Services, now known as Ventia.
A West Australian appeals court last year found Western Power was partially liable for the losses caused by the fire, overturning a previous ruling that apportioned the responsibility entirely to Thiess Services and Campbell.
The Court of Appeal ruled that Western Power breached its duty of care by failing to have a system for the periodic inspection of consumer-owned point of attachment poles used to support the network.
Western Power applied to the High Court to challenge the finding but on Wednesday, the appeal was unanimously dismissed.
"Even though the PA pole was owned by Mrs Campbell, it was Western Power's activities arising from the exercise of those functions and powers that gave rise to the risk of harm if the pole collapsed," the judges said in their findings.
"Although Western Power appeared to accept that it had a duty to exercise reasonable care to minimise the risk of fire arising from its distribution system, it then sought to limit that duty to harm arising only from its own property over which it exercised physical control."
Law firm Slater and Gordon, which led a class action involving 189 victims of the bushfire, said it anticipated further compensation would be available to the claimants as a result of the High Court's decision.
Western Power had sought to recover court costs from victims when it was initially found not to be liable.
Slater and Gordon's Rory Walsh said that attempt had proved to be a waste of public money.
"Having now failed in its attempt to evade liability, Slater and Gordon calls upon the state government to ensure that the additional compensation arising from the High Court decision is promptly provided to the bushfire victims," he said in a statement.
Western Power said it had begun inspecting private power poles when the appeal judgment was delivered last year.
More than 56,000 of an estimated 152,000 poles had been inspected and property owners were notified if maintenance or replacement was required.
"Safety is Western Power's fundamental priority and the High Court's decision adds clarity around responsibilities for private power poles, which is important to ensuring the safety of the community and the electricity system," a spokesperson said.
"We appreciate how difficult this time has been for the Parkerville community. The decision to lodge an appeal against the existing decision did not impede payments to claimants."
