A paranoid schizophrenic who stalked the supermodel Kate Moss stabbed his parents to death after absconding from a psychiatric hospital.
William Warrington, 42, a heavy cannabis user, was detained indefinitely at Broadmoor on Tuesday after he admitted killing his father Clive, 67, and mother Valerie, 73, at their homes in Gloucestershire.
Bristol Crown Court heard how the day before she was killed, Mrs Warrington had sent an email to the secure unit where her son was being held, saying she feared for her safety and that of her other children.
In a victim impact statement read out in court, her family said they had been let down by deficiencies in mental health provision and had repeatedly tried to raise the alarm with the police and the NHS about the danger he posed.
They said: "In the weeks prior our fears for the safety of the family have been communicated to the emergency services, Gloucestershire Police, Gloucestershire Health and Care NHS Foundation Trust.
"The pain of losing our parents is immeasurable and we will carry it every day for the rest of our lives.
"We will forever be affected by the dramatic nature and preventable circumstances which we have been told will be fully investigated by a formal inquiry."
In April 2019, Warrington was handed a non-conviction restraining order, banning him from contacting Moss after leaving unwanted items including a cake and a World War One helmet outside her Cotswolds home.
The court heard how he claimed he believed the model was in telepathic communication with him.
He was admitted to Wotton Lawn acute psychiatric hospital in Gloucester after being arrested for attacking his housemate.
But on the evening of March 2, without the knowledge of the staff, he left the unit and caught a taxi to his mother’s home in Bourton-on-the-Water.
After breaking in while she slept, he attacked her with a knife, slashing her throat, before running over her body in a car.
He then drove the 15 miles to his father’s home in Cheltenham, where he also stabbed him to death.
Warrington was arrested a short time later, telling police he had decided to kill his parents after believing he had been sent messages from the Government, the secret services and Vladimir Putin.
But the court heard Warrington had harboured long held grudges against his parents, blaming them for ruining his life.
He had been receiving treatment for mental health problems since 2016, but in November last year his family became so concerned about his worsening condition that they tried to warn the authorities that he posed a danger to them and others.
On March 1, just hours before she was killed, Mrs Warrington sent an email to Wotton Lawn in which she stated: "I am afraid for the safety of myself, my other children and any others he comes into contact with."
In a victim impact statement read during his sentencing hearing, the family said there were deficiencies in the care of Warrington in the run up to the tragedy.
"William’s mental health has specifically been in decline over the past decade and accelerated due to a deficiency of support in the system," they said.
"When he lost his mind, we lost our brother and then the ultimate tragedy: we lost our mother and father.
"We lost all confidence in the government agencies and systems responsible for managing and responding to mental health crises and domestic abuse. We firmly believe that he continues to pose a severe threat.
"The idea that you might one day be released is horrifying. Again, we are living in fear of our safety."
A spokesman for Gloucestershire Health and Care NHS Trust said: "As well as supporting Gloucestershire Police with their inquiry, we are undertaking our own investigation.
"The outcome will be shared with NHS England and the Care Quality Commission who will further scrutinise this as per national requirements.
"Any learning will be thoroughly addressed, however we will not say anything more until the family has been given the opportunity to be fully updated on the findings."
Warrington admitted the manslaughter of his parents on the grounds of diminished responsibility and was ordered to be detained indefinitely under the Mental Health Act.
