The 16-year-old boy accused of murdering Fico Dougan suffered flashbacks to his own brother's sudden death that may have triggered the fatal stabbing, a psychiatrist told a court this morning.
The teenager, of Mitcham, was tormented by visions of flies swarming near the body of his 28-year-old half-brother, described as "like a father figure", who died in the weeks before the attack.
His legal team argue post-traumatic stress disorder diminished his responsibility in the brutal killing of Fico, a popular 17-year-old student from Thornton Heath who died of a stab wound to the heart following the attack in Ockley Road on September 25 last year.
A jury at the Old Bailey, where the 16-year-old is on trial for murder, heard this morning the accused teen was "not in a good place" after his brother died and had been behaving erratically and drinking "dangerous levels" of alcohol.
Dr Tim Rogers, an expert in adolescent forensic psychiatry called as a witness by defence barrister David Nathan, said he believed the teenager exhibited key signs of severe post-traumatic stress significant enough to impair his self-control.
He told the court: "Post-traumatic stress disorder is reaction to something that is very traumatic and stressful. In my opinion the trauma here is the sudden and unexpected lose of someone in his life, the death of someone who was very significant for him."
The jury heard the defendant's brother had been "a refuge" to him in the absence of his father, who he saw little of after the age of six, and amid "inconsistent" parenting from his mother.
In a report submitted to the court by Dr Rogers, the defendant's mum said he had "broken down crying and wailing" when he learned of his brother's death.
She added: "He would go outside in the back garden and hide it, but I would see him crying. He was more concerned about me but he was not coping."
On one occasion, the defendant was found spinning around in circles in a shopping centre, not responding to the concerns of passers-by.
Dr Rogers said he believed "the horror" of the circumstances in which he learned of his brother's death contributed to his psychiatric problems.
The 16-year-old had visited his brother's house to find the glass pane of his house's front door "full of flies, like a beehive".
Months later, he reported flashbacks to the scene whenever he saw a fly, told doctors he saw the vision while sleeping and said he felt guilty about his brother's death.
Dr Rogers said: "The presence of flies seemed to add an element of horror to it. Although he did not see his brother's body, the horror of what lied beyond added it why it was so traumatic."
He added symptoms associated with psychopathy made the defendant more likely to suffer from post-traumatic stress.
But a second psychiatrist, Dr Phillip Joseph, called by prosecutor Martin Hicks, said be did not believe the defendant had been suffering from the disorder at the time of the killing.
In his report to the court, he suggested the teenager had instead been suffering from "a bereavement reaction" that included dreaming about his brother and struggled to believe what had happened.
He pointed out the defendant had not been diagnosed with post-traumatic stress disorder when assessed following his arrest and said his brother's death was "not sufficiently catastrophic" to trigger the disorder.
The court also heard the defendant had attempted to feign schizophrenic symptoms, including hearing voices in his head, after being arrested.
But Dr Rogers said he was "not a particularly skilled liar" and had failed to convince the nurse assessing him.
The defendant, who cannot be named for legal reasons, denies murder.
The trial continues.