A mother accused of stabbing her two young children was allegedly high on a cocktail of methamphetamine, cannabis and prescription drugs at the time of the incident, a court has heard.
Megan Jayne Somerville, 37, appeared in the Adelaide Supreme Court via video link on Monday from a locked mental health facility.
Somerville has been detained at the facility since the alleged attempted murder of her children, ages three and eight, on the city’s North-South Highway on Aug. 15, 2022.
Emergency services were called to the motorway at around 11.30pm following reports that Somerville had been stopped by members of the public who intervened.
Somerville is alleged to have stopped her silver Honda sedan, pulled her children out of the car and stabbed them “multiple times” with a knife.
The children were rushed to Adelaide’s Women’s and Children’s Hospital where they underwent emergency surgery.
In December 2022, the Modbury Heights mother pleaded not guilty to two counts of attempted murder due to mental incompetence.
But last October, Judge Sandi McDonald heard that Somerville was unlikely to challenge the fact that she allegedly attacked her children, despite reports prepared by the defense that concluded she was mentally incompetent at the time.
Megan Jayne Somerville (pictured) has pleaded not guilty to the attempted murder of her two young children.
Somerville (pictured) allegedly stabbed her two children multiple times on the side of a highway in 2022
Professor Jason White told the court on Monday that Somerville was believed to be a “frequent” or “daily” drug user.
The court heard that significant amounts of illicit and prescription drugs were found in his system both 85 minutes and 14 hours after the alleged stabbings.
Tests found 0.39mg of methylamphetamine per litre of blood, meaning it could have been as high as 0.43mg at 11.30pm.
“The blood sample was found to contain methylamphetamine, which is illegal in Australia. Amphetamine, which is both a therapeutic and illegal drug, was also found,” Professor White told the court.
‘…Therapeutic concentrations (of the drug) are typically in the range of 0.02 to 0.05, so (their results) were approximately ten times higher.’
‘THC, the main active compound in cannabis, was also detected.’
Somerville (pictured) claims she should not be found guilty of attempted murder due to her poor mental health at the time of the alleged attack.
Somerville (pictured) appeared in the Adelaide Supreme Court via video link on Monday morning from a locked mental health facility.
Prescribed antipsychotic medications were also detected.
Professor White believes the high concentration of drugs found in Somerville’s system could have made her impulsive, confused, agitated, paranoid and obsessive.
It also concluded that the drugs may have worsened a non-underlying mental condition, such as schizophrenia.
The court also heard that a friend had testified that Somerville had “obtained” an “8-ball” of methamphetamine the night before the alleged attack.
Judge McDonald will hear further evidence later this week.