A former Army commanding officer was accused today of lying to a public inquiry into the death of an Iraqi civilian in his soldiers' custody.
Colonel Jorge Mendonca said he saw nothing out of the ordinary when he checked on hotel worker Baha Mousa and several of his colleagues after their arrest in Basra, southern Iraq, in 2003.
But Rabinder Singh QC, counsel for Mr Mousa's family and the Iraqis detained with him, questioned his account.
He told the inquiry the senior officer either witnessed a "horrific scene" in the temporary detention facility (TDF) where the Iraqis were being held or never visited them at all.
Father-of-two Mr Mousa, 26, died in the custody of 1st Battalion the Queen's Lancashire Regiment (1QLR) in Basra on September 15 2003, having suffered 93 separate injuries.
Col Mendonca, the former commanding officer of 1QLR, told the inquiry in February that he visited Mr Mousa and the other men held with him on the evening of Sunday September 14.
He said in a statement: "If I had noticed any injuries to any detainees or any of them appearing to be in any distress I would have immediately queried the situation.
"However, there was nothing that alerted me to any type of problem."
Mr Singh, in his closing submissions to the inquiry, raised questions about Col Mendonca's role in the abuse of Mr Mousa and the other detainees.
He alleged that the Iraqi prisoners were beaten by soldiers in the group led by Lieutenant Craig Rodgers, known as a "multiple", before Col Mendonca claimed to have made his visit.
Mr Singh said: "It's not just that he was in overall charge and therefore must take responsibility for what happened on his watch as commanding officer.
"But also there is reason to doubt, frankly, his evidence to this inquiry.
"I have in mind particularly what he told you about his visiting the TDF on Sunday evening at some point - and the timing can be disputed - after the beating by the Rodgers multiple.
"And yet his evidence in effect was that the detainees were quiet and there didn't really seem to be anything worth troubling about.
"Now either of two conclusions may be possible. The first is that he has not told the full truth about what he saw because he must have seen a horrific scene and he should have done something about it.
"Or perhaps what happened was that he never went, as he claims to have done, and realised after the event that he should have done."
Mr Singh agreed with inquiry chairman Sir William Gage that the second possibility was much more unlikely.
Col Mendonca became the most senior British officer to face a court martial in recent history when he was charged with negligently performing a duty in relation to the abuse.
He was cleared in February 2007 and left the Army seven months later, saying he believed he had been "hung out to dry" and made to feel like a "common criminal" by his commanders.
Mr Singh said evidence heard by the inquiry showed that many people passed the TDF while Mr Mousa and the other detainees were being abused there.
He said: "This tells us something, we suggest, about the general environment in which the abuse was able to take place.
"Because, again, many people at least could, and probably did, hear the abuse taking place, and that again tells one something about the culture of impunity that the perpetrators seem to have felt."
Mr Singh singled out evidence that the Iraqi detainees were forced to scream in an orchestrated "choir".
He said: "It is perhaps a terrible glimpse that we have seen at this inquiry of what human beings are capable of, an insight into our heart of darkness."
The inquiry, which started public hearings a year ago, was told that British soldiers used "conditioning" methods on Iraqi prisoners such as hooding, sleep deprivation and making them stand in painful stress positions with their knees bent and hands outstretched.
These techniques were outlawed by the Government in March 1972 after an investigation into interrogation in Northern Ireland.
Then-prime minister Edward Heath told MPs that any future Government wanting to authorise conditioning would probably have to ask Parliament for the powers to do so.
Timothy Langdale QC, counsel for Col Mendonca, said Mr Singh had made "wholly unwarranted" claims about his client.
He said in a written submission to the inquiry: "Those suggestions should plainly be rejected."
Lawyers for other parties involved in the case will also make closing oral submissions this week.
The inquiry will enter its final phase in October, when it will look at what lessons have been learnt since 2003.
Sir William is expected to publish his report around the end of the year.
Today's inquiry hearing in central London was attended by Mr Mousa's father, Iraqi police colonel Daoud Mousa.
He said: "I am in Britain to seek justice and for the truth to be uncovered. To this day there has been no justice or accountability for my son's murder.
"I have been impressed by the way the inquiry has dealt with my son's case and I hope at last to understand after all these years how this could have happened and who was responsible."