WA Police who shot dead hostage-taker cleared of excessive force over Perth siege

Police have been cleared of using excessive force against a hostage-taker shot dead during a siege in Perth.

Officers fired 13 shots in nine seconds, with up to 11 bullets hitting 38-year-old meth user Brendan John Lindsay as he held Sheila Tran captive at knifepoint outside a Carlisle deli in November 2014.

The father-of-one and his partner had been together for about 20 years, planned to have another child and were renovating their home.

But they had argued about his relapses into drug use, which she did not approve of, and which made him aggressive, erratic and sometimes psychotic.

Lindsay's father, John Lindsay, had accompanied his son to drug rehabilitation the day before he died and witnessed the shooting.

He'd noticed his son was becoming increasingly agitated and took him to the lunch bar in a bid to distract him, but became fearful for his safety on the drive there.

Police dog handler Tom Gyrta drove past and spotted Mr Lindsay subtly signal for help, so turned back to assist.

Spotting his father's gesture and seeing the police car, Lindsay became angered and ran into the lunch bar, where he grabbed a kitchen knife and initially pointed it towards his own throat.

Constable Gyrta drew his Taser and ordered Lindsay to drop the knife but he refused, grabbing Ms Tran and holding the knife towards her throat while yelling.

"After the deceased took the hostage, Constable Gyrta considered his firearm to be his only real option, because in his view a non-lethal use of force, if it failed, would have significantly escalated the situation," state coroner Ros Fogliani said in her findings on Wednesday.

The officer repeatedly attempted to negotiate and de-escalate the siege as back up arrived, but Lindsay demanded a helicopter and pressed the knife against the hostage, raising it and shouting he would kill her.

Shots were fired after he stabbed Ms Tran twice in the shoulder.

She also suffered gunshot wounds to her shoulder and leg, and underwent surgery for her injuries.

"Within that volatile and dangerous period there were minimal opportunities for police to de-escalate the situation," Ms Fogliani said.

"He (Constable Gyrta) did try to negotiate with the deceased under very challenging circumstances."