Officers have been heavily criticised by the police watchdog for using handcuffs and leg restraints on a young child with a severe neurological disability.
The girl was arrested several times in 2012 when she was 11.
The watchdog also says officers should have faced misconduct charges.
The Independent Police Complaints Commission has now made a series of recommendations to Sussex Police when dealing with the restraint and detention of children and adults in police custody who are vulnerable and have a mental illness.
The recommendations follow the investigation into the force’s treatment of the girl on five occasions between February 2 and March 2 2012.
The girl - referred to as Child H to protect her identity – has a neurological disability which can cause challenging behaviour, with the potential to harm herself and others.
Child H spent a total of more than 60 hours in police custody after being arrested three times for minor offences, and on another occasion when she was detained under the Mental Health Act.
The girl was held overnight in police cells twice. At the time of the incidents the girl’s neurological disability had not been diagnosed, but the force was informed by her mother that she was believed to be suffering from an autism spectrum disorder.
The IPCC found Sussex Police failed to ensure an appropriate adult – a parent, guardian or social worker - was present to support Child H in custody. Police were also found to have used handcuffs, leg restraints and spit hoods on Child H, yet on a number of occasions did not record any rationale for their use of force.
The investigation found these failings were in part due to Sussex Police’s training and force policy. Shortly after the IPCC investigation started, Sussex Police took early steps to establish appropriate protocols with Child H’s family to ensure lessons were learned and changes implemented in any future dealings with her.
The IPCC’s recommendations to the force include improved training on the use of force on children and adults with mental illness, to ensure the use of force is avoided wherever possible; additional training on detaining vulnerable people and the role of an AA; and ensuring officers are accountable for their use of force.
IPCC Commissioner Jennifer Izekor said, “This was a complex investigation, which found Sussex Police officers failed to respond effectively to the needs of a vulnerable child.
“While it is clear Child H had significant behavioural problems arising from her disability, Sussex Police and, indeed other agencies which were – or should have been - involved, did not appear to have the skills and capacity to respond to her effectively. The situation was exacerbated by the lack of understanding of Child H’s complex needs.
“The IPCC understands it is not possible to train each and every frontline officer to recognise and understand the complexities of all emotional or behavioural issues. But it is important that officers responding to young people with mental health, emotional and behavioural difficulties have a basic understanding of their needs and how best to deal them.
“I was pleased that shortly after we began our investigation the force engaged with Child H’s family to establish appropriate protocols to ensure that lessons were learned and changes implemented in any future dealings with her.
“We welcome the changes Sussex Police has made to its training and processes since the start of our investigation.”
The IPCC’s view was there was a case to answer for misconduct for six custody sergeants for failing to ensure an AA was present, one of whom also failed to transfer relevant information onto the risk assessment; another custody sergeant for failing to ensure that Child H was dealt with expediently whilst in custody; and two police constables for their restraint of Child H in handcuffs.
Conduct issues identified during the course of the investigation have been addressed by Sussex Police through management advice.
Two further officers - a custody sergeant and an inspector - who in the IPCC’s view would have had a case to answer for misconduct for failing to ensure an AA was present, have since retired.
No further action was taken against a former front desk enquiry officer who the IPCC believed had a case to answer for misconduct for failing to treat Child H’s mother according to her needs; a call handler for failing to log sufficient information about Child H’s condition; and against a police constable who, in the view of the investigator, had a case to answer for misconduct.
After the findings Temporary Deputy Chief Constable Robin Smith said, “We take our responsibility for any use of force very seriously particularly when it involves young people or those who are vulnerable.
“We welcome the IPCC’s scrutiny and during its investigation the Force has adopted many schemes to support vulnerable people and those with mental illness, learning disabilities and substance misuse issues. Aspects of our approach are being held as good practice nationally and we will respond to any new learning identified in the IPCC’s report.
“A lot has been achieved to support people who are vulnerable, however we cannot be complacent and will continue to work with partners to ensure that the right decisions are made in assessing and supporting those who need it.
“As a direct result of the investigation into this case, personal safety and first aid training, which all officers have to undertake, has been updated. This means officers have learned communication skills to help them be more effective when helping people with mental illness. In addition all officers have refreshed their knowledge in the use of spit guards.
“As a chief officer I have a duty to protect officers and the public when we are called on for help, whether the threat comes from a child or someone who is unwell. This is very often the case and it was on several occasions that the girl’s mother called for our help. The application of any type of restraint is considered only when the level of resistance causes concern for the safety of the detained person, the officer and other members of the public.”