A man who died in a head-on crash with a truck was under a mental healthcare order and had dangerous levels of anti-psychotic drugs in his system, an inquest has heard.
The ACT Coroner's Court is exploring the circumstances of the death of Ben Williams on September 28, 2010. The inquest has heard Mr Williams had a ''lethal'' level of one drug and a ''toxic'' level of another on the day of the crash.
Mr Williams was behind the wheel of a southbound hatchback that crossed onto the wrong side of the Monaro Highway two kilometres south of Calwell. His car crashed into a fully laden timber truck travelling in the opposite direction.
A crash-scene investigator on Monday told the inquest there was no evidence Mr Williams tried to apply the brakes in the moments before the impact. ''Almost all [witnesses] were consistent that the vehicle driven by the deceased swerved quite violently in front of the oncoming truck,'' he said.
One motorist described seeing smoke coming from the exhaust of the diesel, which the officer said was consistent with acceleration. The truck driver, who was uninjured, told police he saw Mr Williams ''sitting straight up in the driver's seat .. and he appeared to be driving normally''.
The court heard Mr Williams, 30, had been on a psychiatric treatment order for most of the period between 2006 and his death.
Bruno Aloisi, a psychologist with a co-ordination role in ACT Health's community mental health teams, told the court he had no direct contact with Mr Williams. But he told the court he understood diagnoses of a psychotic disorder, schizophrenia and a schizoaffective disorder had been suggested.
Mr Williams' psychiatric treatment order - a step taken only if all voluntary treatment options have been exhausted - was extended just five days before his death. And at the time of the crash he was on a combination of the anti-psychotic drugs Clopixol and Olanzapine.
The court heard at some point a decision had been made to allow Mr Williams to take control of at least part of his medication regime. But a report showed high levels of both drugs in his system.
Associate Professor Graham Starmer, a pharmacologist from the University of Sydney, said Mr Williams' Olanzapine level was 20 times what he would have expected given his prescribed dose.
Professor Starmer said the reading was ''in the lethal range''. He said Mr Williams' blood showed a higher level of Clopixol in his blood than would be consistent with his proper dosage - ''in the toxic range''.
''I would be surprised if the drug had been given at a much higher dosage on a regular basis by health professionals .. it's a possibility of course,'' Professor Starmer said.
He said Mr Williams could have been capable of rational thought and planning despite the drugs in his system. He also suggested the inquest should explore the reasons for the prescription of the two drugs and how the medication regime was monitored. The hearing before Chief Coroner Lorraine Walker continues on Tuesday.
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