In spite of an absolute prohibition within the Nelson Mandela rules – the standard minimum rules on the treatment of prisoners – the international and European legal framework surrounding its use is unclear. There is no case law at the European Court of Human Rights level which deals with the issue.

Addressing this would allow a strong response against the practice, Dr Christine Bicknell, from the University of Exeter Law School, claims. Dr Bicknell joined experts from across the world to discuss the issues relating to detention and issues in prisons at an event held as part of a large project run by the University of Ghent.

Her research tracks trends in the use of juvenile solitary confinement, which is lawful across many European states.

She has identified dominant trends in its use: informal or mislabelled use, as a disciplinary offence or to prevent self-harming or violence from other children or because the authorities cannot think of another safe way to detain the young person. The situation is made worse by corruption in prisons or use when children are on remand.

Dr Bicknell said: “Detained juveniles have triple vulnerability: as a child, being detained and isolated. In spite of its dangerousness, I have found isolation is sometimes used as an attempt to protect from harm and to safeguard those with complex needs. It is however often used as a disciplinary measure, including in some post-Soviet states to sanction children who are self-harming. Even more complicated are documented instances of children self-harming deliberately to be placed in isolation, thereby avoiding wider inter-juvenile violence.

“There is an emerging body of international law and neuroscience which suggests juvenile solitary confinement should be prohibited, however ‘soft’ law is increasingly used to govern its use. There is a tendency for European states to legally mislabel the practice and at an institutional level there can be confusion over how to categorise it. 

“Juvenile solitary confinement is capable of causing serious and irreversible harm and this informs the dominant view in international law that it constitutes the sort of ill-treatment prohibited absolutely - that is, it can never be used and there is never justification for its use - under the International Covenant on Civil and Political Rights and the United Nations Convention Against Torture.”

The case of a 15-year-old with complex needs, who was held on his own in the UK for 55 days consecutively, was brought to the European Court of Human Rights. In December 2023 the UK government accepted that it had breached the ECHR and made a ‘friendly settlement’, suggesting the use of solitary confinement in the UK at least, may be approached more cautiously going forward. Dr Bicknell said in many ways a concrete decision from the court would have been helpful to solidify the standards as they are emerging within Europe.

Because of the opaque international and European standards, there remains uncertainty as to the lawfulness of juvenile solitary confinement within Europe. Authorities also face the practical difficulties sometimes face of simply not knowing what else they can do with a certain child.

Dr Bicknell said: “There is a need for both detailed research and dialogue between international and European institutions with safeguarding and standard-setting functions to establish a clear, consistent, comprehensive and evidence-based position as to when, in what circumstances, and bound by what baseline rules juvenile solitary confinement might be, if it is ever, - considered lawful. It is important to point out that empiricists with direct experience of this are generally of the strong view the practice should never happen, and the Mandela rules also make this clear. The European Committee on the Prevention of Torture presents a more nuanced approach and this is indisputably a complex matter.

“Improved clarity in the applicable standards would help address the frequent disjoin between law and practice, and the mis-labelling of it as some other practice. By consequence of correct categorisation, improved safeguards would in some states inevitably become more available.”