Teenage killer should not have been released by hospital staff: psychiatrist
An Ellenbrook teenager who stabbed his mother, sister and brother to death in 2018 was not assessed by a psychiatrist or admitted to hospital after police took him there under the Mental Health Act the night before the killings, a Perth court has heard.
Teancum Petersen-Crofts, 21, has pleaded not guilty due to unsoundness of mind to the murders of Michelle Petersen, 48, and his siblings, Bella, 15, and Rua, 8, on July 14, 2018.
Teancum Petersen-Crofts is accused of murdering his mother, Michelle Petersen, and two siblings in 2018.
At the time, he was suffering multiple delusions including hearing voices in his head commanding him to kill his family.
During the opening day of his Supreme Court trial on Friday, Chief Justice Peter Quinlan was told of Ms Petersen’s repeated attempts to get her son mental health support, with his first hospital admission at 15 years old.
He went on to be admitted to hospital a further 11 times with psychotic symptoms, and was seen many more times in various emergency departments over the following three years before killing his family when he was 18.
Forensic psychiatrist, Daniel de Klerk, diagnosed Mr Petersen-Crofts with paranoid schizophrenia and said his presentation to St John of God Hospital Midland the night before the deaths should have been taken more seriously.
“In the first instance, hindsight is 20/20, however, in saying that, in a young man with repeated hospital admissions ... and talking about being followed by serial killers, the outcome could have been very different if he had been admitted,” he said.
“He was not assessed by a psychiatrist, which would have been my first expectation.
“People with psychosis do not walk around with a sign saying, ‘I have psychosis’... he should have been taken more seriously.”
Instead, Dr de Klerk said the assessing emergency department physician assessed Mr Petersen-Croft’s walk, and decided he was not in psychosis – a method not used by psychiatrists.
He was held over night at the hospital and released in the morning – the day of the deaths.
Mr Petersen-Crofts, who has been held in Frankland Centre since his arrest, remains very unwell and continues to suffer hallucinations in 2021 despite being on medication.
Dr de Klerk concluded the teenager was likely part of around one third of people diagnosed with paranoid schizophrenia who do not respond to treatment.
Forensic psychiatrist, Steve Patchett, who also gave evidence at trial, said the younger a person was when they first developed psychotic behaviours, the more severe the hallucinations and delusions tended to be.
“This is a very tragic story due to the level of psychosis at a very young age,” he said.
“Despite all the best evidence-based medicines available, some people don’t respond and that is the situation here.”
Dr Patchett said Mr Petersen-Crofts was extremely remorseful for his actions.
“He sat on the couch for half an hour [before the deaths] and he really agonised, trying to stop [the voices in his head, commanding him to kill],” he said.
“He believed he had to.
“He will say, ‘I did it, I killed my mother, my sister and my half-brother’, but he gets very distressed ... he cries, I’ve seen him sobbing.
“He talks a lot about how he loves his family and feels intense remorse for what he’s done.”
Both forensic psychiatrists concluded Mr Petersen-Crofts was not in control of his actions the day of the deaths, and was suffering powerful hallucinations.
The state and Mr Petersen-Croft’s lawyer are also in agreement the evidence leaves it open for Justice Quinlan to find he was of unsound mind when he killed his family members.
After a two-day trial, Justice Quinlan is expected to deliver his verdict at 2.15pm.
Mr Petersen-Croft’s family was in court to hear the evidence.
The 21-year-old sat mostly with his head down during proceedings, looking up only to wave and smile at a family member during a break.
Heather McNeill is a senior journalist at WAtoday.