The Supreme Court will this week host the latest chapter in a long-running legal saga about how detainees should be held abroad by the UK.
Lawyers will argue over the legal framework which applies when the UK detains people while assisting other states in maintaining security during periods of internal armed conflict.
The one-day evidence session in Serdar Mohammed v MoD will focus on whether the UK failed to put in place procedural safeguards when Afghan national Mohammed was detained by British troops in 2010.
The suspected Taliban insurgent was held without charge and without access to a lawyer for 110 days, before he was handed over to the Afghan security services.
There it is alleged he was tortured and forced to thumbprint a document which confirmed he had confessed to being a Taleb.
He was later convicted by an Afghan court following a trial which Mohammed says he did not understand and was released from detention in Afghanistan in 2014.
In July 2015, Court of Appeal judges ruled unanimously that UN Security Council Resolution 1890 permits detention for only 96 hours before detainees had to be transferred to local authorities. The court found that British forces had no authority to detain Mohammed beyond these 96 hours.
In February, the Supreme Court heard arguments about whether British forces had the legal power to detain Mohammed without charge.
Tomorrow, the law lords will hear arguments about whether the MoD failed to put in place essential procedural safeguards and whether any such failure rendered Mohammed’s detention unlawful.
A spokesperson for Leigh Day, representing the Afghan national, said 'We are hopeful that the Supreme Court will recognise the fundamental importance of the rule of law especially in situations of internal armed conflict where instilling law and order is the primary objective of the British forces.
‘We will be arguing that there needs to be a lawful authority for any detention and for core procedural safeguards to be afforded to a detainee to prevent detention from becoming arbitrary.’
The case comes at a time when the Ministry of Defence has been a vocal critic of firms such as Leigh Day running cases on behalf of civilians in conflict-affected countries abroad.
Measures are being drawn up to restrict these types of claims, and Leigh Day itself is subject to ongoing proceedings at the Solicitors Disciplinary Tribunal over its conduct in running claims against the MoD in the past. The firm denies any wrongdoing and a hearing is expected next year.