The High Court in London is hearing a case lodged by six Iraqi families, who say British troops in Iraq unlawfully killed their loved ones.
The High Court is being asked to order a full, independent judicial inquiry under British law into the six deaths.
A lawyer for the Iraqi families, Phil Shiner, says the deaths occurred after major combat operations had ended in May of last year, and should be handled as if they had occurred in Britain.
"I want to emphasize that these cases did not arise from the war," he said. "All these incidents took place while the U.K. armed forces occupied southeast Iraq. As a matter of law, we say that if a man was beaten to death in detention in Iraq, there's no difference compared with the situation if he'd been beaten to death in London."
Lawyers for the British defense ministry say the armed forces legal system has dealt with the cases, and it would be wrong to apply British laws or European human rights conventions to events in Iraq.
Among the deaths the court is considering is that of Baha Mousa, a 26-year-old hotel clerk, who died in British custody in Basra last September. His family says the corpse showed signs of a severe beating. The family has rejected a British offer of $5,000 compensation, calling it an insult.
A colleague of Mr. Mousa, Kifah Taha al-Mutari, has come to London to testify.
Mr. al-Mutari says he was detained along with Mr. Mousa, and was beaten so badly over three days that he nearly died. He describes his treatment as "inhumane, illegal and unjustified."
The High Court is expected to hear testimony for two or three days before considering its decision.