It is a part of Mersey Care NHS Foundation Trust, catering to patients with psychiatric health needs that require treatment in conditions of high security.

For Scotland and Northern Ireland, the facility meeting the same high security environment is the State Hospital in Carstairs.

Ashworth is one of the three high-security psychiatric hospitals in England and Wales, alongside Rampton and Broadmoor, that exist to work with people who require treatment due to their "dangerous, violent or criminal propensities", with the majority experiencing psychotic conditions such as schizophrenia,[1] comorbid or other personality disorders.

[5] Rehabilitative and creative activity is supported with patients frequently entering work for the Koestler awards winning 27 prizes in 2011.

[8][9] The hospital has its origins in Moss Side House, a convalescent home for children from Liverpool's workhouses, which was established on the site in 1878.

[16] In 1997, a patient absconded from a day rehabilitation trip in protest against his treatment and the management of the Personality Disorder Unit.

The inquiry found that Child A had visited the hospital on hundreds of occasions and had spent periods dressed only in her underwear with a patient with a history of violent sexual assaults against young girls.

Child A's father also took the young son of a friend to visit a second patient found guilty of kidnapping, sexual torture, mutilation, and murder of a 13-year-old boy.

The inquiry team reported that Dr John Reed, chairman of the Reed Committee on Mentally Disordered Offenders, described a conversation with Prof Pamela Taylor, then head of medical services of the special hospitals, in which the doctors at Ashworth were described as follows.

[21][22] As part of the 2016 review of the United Kingdom as a whole the European Committee for the Prevention of Torture and Inhuman or Degrading treatment or Punishment visited Ashworth Hospital.

The CPT expressed misgiving about the use of overwhelming force deployed at Ashworth including the use of personal protective equipment, helmets and shields.

The committee considered that the systematic locking-in of patients, amounting to ten hours of de facto seclusion, was not acceptable in a care establishment provided there was sufficient staff.