A team of retired British detectives is carrying out a unique investigation for a public inquiry examining allegations that UK soldiers killed and tortured civilians in Iraq.
The Al-Sweady Inquiry is looking into claims that 20 or more Iraqis were murdered and others suffered horrific abuse after the "Battle of Danny Boy" in southern Iraq in 2004.
The inquiry has appointed a squad of ex-British police officers headed by former top Scotland Yard murder detective Stephen Condon to carry out the first detailed investigation into the allegations. They are effectively starting with a blank sheet after an earlier Royal Military Police inquiry was judged to be inadequate – it is not even clear how many Iraqis are alleged to have been killed.
This is believed to be a first for a public inquiry, which would normally take a fresh look at events that had already been closely examined.
The inquiry is named after 19-year-old Hamid Al-Sweady, one of those who died following a gunfight between UK soldiers and Iraqi insurgents at a checkpoint in Iraq's Maysan Province known as "Danny Boy" on May 14 2004.
It was launched as a result of a High Court fight against the MoD by Mr Al-Sweady's uncle and five Iraqis who say they were abused by British troops after the battle.
The inquiry's terms of reference cover investigating and reporting on allegations against British soldiers of unlawful killing at a UK base called Camp Abu Naji on May 14 and 15 2004, and of ill-treatment of five Iraqis between May 14 and September 23 2004.
The MoD vigorously denies the allegations and says those who died were killed on the battlefield.
An inquiry spokesman said: "We're starting with a set of allegations which have not been properly investigated. So therefore the inquiry itself has had to try to do that investigation.
"The first thing we've had to do is to interview the Iraqis to actually formalise what the allegations are. We've got these generic allegations but there's no specifics there. It's being run effectively as a murder inquiry. But because of the nature of it as a public inquiry, we don't have any formal powers. Our team are retired police officers and they don't have any powers, so it has to be run slightly differently – we can't force people to speak to us."
Because of the dangers of travelling to Iraq and the problems of getting Iraqi witnesses visas to come to Britain, the ex-detectives have been conducting their interviews in Beirut, Lebanon.
But concerns about the political situation in Lebanon mean the Al-Sweady Inquiry team is currently looking at moving to another country to carry out their work.
The possibility of disruption to the investigation's timetable is a concern because the inquiry, chaired by former High Court judge Sir Thayne Forbes, is costing about 500,000 a month.
The ex-police officers have identified 100 Iraqi witnesses, including nine alleged torture victims, eyewitnesses, medical staff and relatives of the dead who can give evidence about the state of the bodies. A total of 35 of them have now been interviewed, and it is likely to take until the end of September to complete the process.
The spokesman said the inquiry had the "full co-operation" of the Iraqi witnesses.
Attorney General Dominic Grieve has agreed to grant witnesses to the inquiry immunity from prosecution based on their own evidence.
The inquiry spokesman stressed the team was keeping an open mind about the case. "What we have always said is we will investigate this thoroughly and it will take us where it takes us.
"We are independent of Government. If the evidence suggests that there was wrong-doing by British soldiers, we will follow that evidence. Equally if the evidence suggests that this is just an attempt by some Iraqis to get some compensation out of the British Government, that's what we will come up with."