Hertfordshire police have concluded their investigation into reports of excessive use of sedation and non-recent sexual assaults against children who had stayed at Hill End Adolescent Unit a mental health facility in St Albans.

The constabulary has announced that no charges will be brought as a result of the three-year inquiry by the Major Crime Unit into sedation and sexual abuse at the unit between 1969 and 1995.

They said officers had established that the use of sedation at the Unit did not meet the standards of the day and medical records show that in some cases children were given adult doses and were repeatedly sedated. However, there is insufficient evidence to support any arrest or prosecution.

They said that while no arrests were made, a total of 70 former staff members were traced and witness statements obtained. Where available, medical records were recovered and examined, but the passage of time meant many records were no longer available.

As well as the use of sedation, the constabulary said that officers had also investigated allegations of sexual assault at Hill End. These had all been fully investigated however, again there was insufficient evidence to support any arrest or prosecution.

Detective Superintendent Jerome Kent said:

"We know that this has been a long process but we had a fundamental responsibility to all those involved to fully investigate the allegations in relation to Hill End Hospital Adolescent Unit. Non-recent cases are always challenging and those who stayed at the unit have been incredibly courageous in speaking to officers about their experiences.

"Myself and the investigation team would like to thank them for speaking out and we understand that doing so will have brought back many distressing feelings and that this process will have caused many to re-live the trauma of their time at Hill End.

"While the investigation is unable to progress further for the reasons outlined, we hope that those who came forward to share their accounts with us will find some closure in the knowledge that they have been listened to, taken seriously, and a full and proper investigation has taken place."

Leigh Day represents 60 clients whose cases were stayed while the police investigation was ongoing.

Solicitor Emma Jones said:

"Although it is disappointing the police have decided not to take this further, the fact that the seriousness of the issues raised resulted in this investigation I hope will go some way to my clients feeling vindicated.

"It is clear from the statement that children were over sedated. Officers established that the use of sedation at the Unit did not meet the standards of the day and medical records show that in some cases children were given adult doses and were repeatedly sedated. These are incredibly serious issues – children being subjected to, what I would say was a "chemical cosh".

"This makes clear that the police found evidence to support these allegations made by my clients and others. Now the criminal investigation has concluded, we will begin the investigation of the civil claim."

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