A youth custodial officer on trial for allegedly assaulting a teenager inside WA's Banksia Hill detention centre says he feared he was going to be attacked by the teenager.
Mark Thomas Griffen, 57, is accused of using excessive force when he pulled the teenager to the floor in May 2022.
"There was no need for that force to occur," police prosecutor Nick Humphrey told Armadale Magistrates Court today.
"It's over the top."
Defence lawyer Andrew Tehan told the court Mr Griffen was "authorised to act" in the way he did.
He said the teenager had a history of behaviour that was "non-compliant" and "verbally threatening".
Incident captured on CCTV
The court was shown video of the boy refusing to get on to an orange box so he could be searched with a hand held metal detector.
The court was told he'd just returned from the Children's Court and had been brought back early because he was "acting up".
Soon after getting on the orange box, he could be seen leaning very close towards Mr Griffen who then pulled him down.
The court was told the youth had a history of incidents, including spitting, punching, kicking, headbutting, throwing urine and threatening staff at Banksia Hill and the Children's Court.
The teenager, giving evidence via video-link, admitted he had threatened and abused Mr Griffen at Banksia Hill on the day in question.
He told the court that soon after arriving at the detention centre, an officer "grabbed" him and he responded by saying "leave me alone you motherf*****".
Then he was told he needed to be searched with a metal detector wand, and would need to stand on a box.
"I was getting agitated," he told the court, and said he remembered "getting slung on the floor".
The teenager said he "got winded" and "couldn't breathe" for about 10 seconds.
He told the court he felt "sad and p***ed off" and was a bit sore for a couple of days after the incident.
The 15-year-old said he had some trouble remembering everything because he'd since suffered head injuries due to motorbike crashes.
Threatening language used
Under questioning from Mr Tehan, the teenager denied he didn't want to be searched because he had a piece of metal from a seat belt with him, taken from the van.
The court heard he'd covered cameras in the vehicle.
He did admit to telling Mr Griffen "I'll bash you, you old dog" and "you motherf*****, don't f*** around, I'll king hit you".
The teenager said he said that to scare him.
When Mr Tehan asked if he'd been held around his shoulder and back with hands on his arms, the boy responded that he'd been grabbed on the neck.
Statements from other custodial officers described how they saw the teenager lunge at Mr Griffen, calling him an "old c***" and threatening to "punch his head in".
Statements also referred to a lack of custodial staff placing pressure on officers.
One officer said the teenager spat out an object that looked like it was from a seat belt.
Officer believed he would be assaulted
In his evidence, Mr Griffen said there were no admission staff members at Banksia on the day.
"Should've been three, but was zero," he said.
"Short staffing is the issue, the movements coordinator's workload is massive."
He said the teenager's behaviour at the detention centre had been escalating over time.
"Assaulting staff and property damage would be a daily occurrence," he said.
Mr Griffen told the court that when the youth got out of the van, he was trying to "keep it light, jovial", while telling him "we're going to do a wand search, a pat search".
He said the boy responded "f*** you, I'm not getting a pat search, I'm not getting a wand search", and continued to abuse him.
"I've asked him to stand on the box," Mr Griffen told the court, and said another officer was helping try to "de-escalate" the situation.
When the video was played again and Mr Griffen was asked about the moment he held the boy, he became emotional.
Following a break, he returned to the stand and said that when the teenager leaned into his face, he used the "seat belt hold", or "harness hold", because he believed he was at risk of being assaulted.
Mr Griffen told the court the juvenile was a "prolific spitter" and had assaulted guards by headbutting.
After the May incident, he told the court, an "email came out saying the box was not to be used under any circumstances".
'Disproportionate' force used
The court heard there was no specific training for guards dealing with the height issues created by using the box for detainees to stand on.
Summing up, Sergeant Humphrey said it was "not the prosecution case that force should not have been used", but that the force used was "disproportionate".
He told the court the prosecution was not seeking a term of imprisonment as a penalty.
Andrew Tehan said Mr Griffen had done his job "dutifully" for many years and now found himself in court, and under media scrutiny, because of a split-second decision.
He told the court his client acted because he believed he was at imminent risk of injury.
Magistrate Brian Mahon said it was a "simplistic view to say the video is the answer" to the case.
"These are challenging matters," the magistrate said.
Magistrate Mahon said he would hand down his verdict in early May, if not before.
