Jamahl Mclean faces Port Augusta District Court after stabbing his aunt in the back

A 22-year-old man who stabbed his aunt in the back, after a similar previous attack by her husband, says a marijuana-induced psychosis was to blame.

A Port Augusta man who stabbed his aunt in the back has blamed marijuana-induced psychosis for his actions.

Jamahl Mclean, 22, faced the Port Augusta District Court for sentencing submissions after he committed the vicious attack on September 11, 2020.

According to his lawyer, Sally Burgess, after stabbing the victim, he experienced a psychotic episode.

“Mr Mclean was looking at his phone and expressing a delusional belief that people were watching him through his phone,” Ms Burgess said.

“Including belief that messages are transmitted through things such as the television. He had recently been in hospital with drug-induced psychosis.

Ms Burgess said because Mclean’s psychosis was self-induced they couldn’t apply for a mental incompetence defence.

Mclean’s aunt did not file an impact statement following the stabbing.

The court heard Mclean’s aunt was also previously stabbed by her own husband, who “ironically” served time for the crime in custody while Mclean was on remand in custody in a Port Augusta jail.

“His uncle spent the best part of six months in jail for stabbing her as well,” Ms Burgess said.

“To stab someone in the back is serious, it’s fortunate that his aunty was not more seriously hurt,” said Ms Burgess.

“It was hard for me to assess his schizophrenia diagnosis, it does appear that that’s the case but it doesn’t appear that it was that being exacerbated from the marijuana, that’s led to this.

“There is quite an extensive history of problems with Mclean, stemming from this drug and resulting in violent episodes and strange episodes.”

Prosecutor Sarah Hennigs said Mclean had made no effort to engage in treatment for his psychosis and has a tendency to resolve conflict through aggression.

“In my submission it (marijuana) should not reduce the culpability in the same way that someone consuming alcohol doesn’t reduce culpability,” Ms Hennigs said.

“The offending is not as serious as a premeditated offending but shows that there’s risk of reoffending and reoffending in a serious way.”

His lawyer, Sally Burgess, concluded by highlighting Mclean’s previous escalating issue with marijuana.

“It’s rather an unfortunate scenario as he heard that it could assist with sleep but instead became addicted,” Ms Burgess said.

“He started using pot recreationally in 2016 but in 2018-2019 started using in a way where he has now become dependant.”

Judge Gordon Barrett was asked to consider a suspended sentence for the offence, citing Mclean’s dependence on weed and a lack of suitable address available for home detention.

Mclean is due for sentence later this month.