The Ministry of Defence operated "flagrantly" outside the laws on detention, a spokesman from lawyers Leigh Day said.
The law firm, who represent Afghan farmer Serdar Mohammed in his damages claim for assault, false imprisonment and human rights breaches against the Government, made the comment after the High Court ruled UK forces' detention policy in Afghanistan was unlawful.
When we send our troops abroad it is the Ministry of Defence's job to ensure that the mechanisms are put in place to ensure that they operate within the rule of law.
As the court has made clear, the MoD fully understood the parameters of the law regarding detention and yet they decided to operate flagrantly outside those rules.
More top news
Facebook has completed its first test of a solar-powered drone that carries internet signal in the skies above the UK.
Russia goalkeeper Igor Akinfeev has thanks fans for their support after he was struck by a flare thrown during a qualifier in Montenegro.
Astronauts arriving for their new mission hug the crew on arrival at the International Space Station.