The case of a boy who has been held in solitary confinement at Feltham prison will be heard in the High Court on Tuesday (April 25).
A judicial review has been brought by Howard League for Penal Reform over the confinement of the boy, at the Feltham Young Offenders Institution (FYOI), which it argues is unlawful.
Only identified as AB, the boy has been locked up alone in his cell for 23 and-a-half hours a day, meaning he got 30 minutes out of his cell a day, and has been denied any educational provision.
A legal team at the charity applied for a judicial review in February, and will represent the boy at the Royal Courts of Justice.
Earlier this year the government admitted that for long periods of the boy's time in custody, aspects of his treatment were unlawful.
The Equality and Human Rights Commission has been granted permission to intervene in the case.
Frances Crook, chief executive of the Howard League for Penal Reform, said: “This is a widespread problem and it is getting worse.
"In just the last week, several more children, held in prisons across the country, have asked the Howard League for help because they are in almost total isolation.
“Some of the children we have represented have been in solitary confinement for up to nine months and have been subject to very similar regimes to the boy in this case.
"They have been allowed out of their cells for about 30 minutes a day, with little or no access to education, limited access to exercise or fresh air, and no association or meaningful intervention.”
The charity says the UK is out of sync with international consensus that children should not be placed in isolation.
There is evidence to suggest prolonged confinement can have lasting effects on a child's mental health.
In an annual report for 2014-15, HM Chief Inspector of Prisons reported in Feltham “26% of the population were being managed on units under a restricted regime that excluded them from activities and meant that they were unlocked for less than an hour a day – in effect, solitary confinement on their residential units”.
The legal case for AB argues his treatment is in breach of the United Nations’ Mandela Rules, which prohibit the use of solitary confinement for children.
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