A British banker accused of killing two women in Hong Kong had been diagnosed with narcissistic personality disorder and sexual sadism, the court has heard.
A medical witness for the defence said Mr Jutting also suffered from the effects of cocaine and alcohol abuse.
Mr Jutting has pleaded not guilty to murdering Sumarti Ningsih and Seneng Mujasih in 2014 on the grounds of diminished responsibility.
He did plead guilty to manslaughter, but the prosecution rejected that.
Defence witness Richard Latham, a consulting forensic psychiatrist in the UK’s National Health Service, said Mr Jutting’s disorders had progressed to the “most severe end of the spectrum” by the time of the killings.
His ability to control his behaviour was “substantially impaired”, Mr Latham said.
Mr Jutting’s defence lawyer, Tim Owen, said his client had had a troubled upbringing.
He was sexually abused during his boarding school days at the prestigious Winchester College in the UK, and his father killed himself when he was 16, he said.
The court has previously been shown videos showing Mr Jutting torturing Sumarti Ningsih, 23.
In other videos filmed on his iPhone, Mr Jutting also takes cocaine, consumes alcohol and explains the reasons why he tortures women.
The trial is continuing in Hong Kong. Mr Jutting faces a possible life sentence if convicted of murder.
The gruesome details of the murder case has captured international attention. It is also the biggest murder trial in Hong Kong in years, as the city is considered one of the safest in the world.
Rurik Jutting had narcissistic disorder, defence says}