Eight or more civilians died in the custody of British troops in the weeks after the invasion of Iraq, despite frequent warnings by the army's most senior legal adviser there about unlawful treatment of detainees, the inquiry heard. Gage heard evidence that military and civilian officials tried to downplay the significance of Mousa's death and dissembled when MPs asked about the circumstances surrounding it. These are international obligations. This is what we demand of others, but we do not demand it of ourselves. What kind of message does that give to the world about who we are?"

May 2004: Amid reports of several cases of abuse by British soldiers against Iraqi civilians, Geoff Hoon, the then defence secretary, says a decision is pending on whether to take action against any soldiers involved in Mousa's death. Shortly before his death, Mousa's 22-year-old wife had died of cancer. His death meant his two young sons, Hussein and Hassan, were left as orphans. Third was a "rolling programme of strike operations" to apprehend civilians –"blowing doors off so that 20 soldiers can run into houses at one or two in the morning while women and children are sleeping, men dragged from bed and rifle-butted – one man was simply shot in bed – women and children abused".A bloody epitaph to Blair's war". Independent on Sunday. London. 17 June 2007. Archived from the original on 2007-06-19 . Retrieved 2007-06-18. December 2005: The court of appeal rules that an "independent and effective" inquiry must be held into how Mousa died, upholding the earlier high court decision. The MoD takes the case to the House of Lords.

Singh 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." Human rights groups and lawyers representing former prisoners are pushing for a public inquiry into British detention and interrogation practices in Iraq, which would trace responsibility for the abuse up the military chain of command and beyond, and shed light on the role played by military physicians.

Williams's book, A Very British Killing: the Death of Baha Mousa, details the killing and flawed investigation and prosecutions which followed, and exposes what he calls "a culture of callous indifference that infected a whole battalion and permeated far up the command chain, both military and governmental. What happened to Baha Mousa, and how the army and the government responded to his death, is emblematic of a whole system in operation."

The legal issue at stake is whether the other abuses were isolated incidents of which commanders were unaware, as the government insists, or systemic and authorised as policy. With these cases comes the contention that the violations were systemic and thereby illegal – with responsibility reaching senior command level – which would put the state in breach of international law and necessitate an independent public inquiry. The victims' claim before the court says: "No Iraqi appeared to be exempt from ill-treatment from arrest onwards." The report finds that a series of brutal acts by members of British forces led directly to the death of Baha Mousa; others were involved in assaulting him and his fellow detainees. Civilians say they were subjected to hooding, beating, threats of rape and execution, forced nakedness and maintaining stress positions, violence against wives and children, ritual humiliation. And they claim that others, like Baha Mousa, were beaten to death. They say walls of noise were used to drive the prisoners mad and cover the sounds of abuse and pain.

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However, speaking exclusively to the Observer, Madden said Gage's criticism and the evidence unearthed by the retired appeal court judge during his 12-month inquiry were "mistaken".

October 2008: The public inquiry chairman, Sir William Gage, makes an opening statement in which he reveals that the soldiers have been granted immunity from prosecution based on their evidence to the hearings. Corporal Donald Payne was jailed for a year and dismissed from the army after pleading guilty to inhumane treatment of Mousa. The six others either had the charges dropped or were acquitted.It is clear from the inquiry report that we were ill-prepared in 2003 for the task of handling civilian detainees. The Army has made strenuous efforts since then to transform the way we train for and conduct detention operations. The MPTS said he engaged in "misleading and dishonest" conduct when, at courts martial and a subsequent public inquiry, he maintained under oath he saw no injuries to Mousa's body. February 2010 Giving evidence to the inquiry, Mendonca accepts responsibility for Mousa's death but says the tragedy was a "one-off" and insists he left Basra a better place. April 2007: Payne is jailed for a year and dismissed from the army. He is cleared of manslaughter because it cannot be proved he inflicted the fatal injuries. On 14 September 2003 Mousa and other detainees were brought in for questioning after being arrested at the Ibn Al Haitham hotel in Basra in the early hours of the morning.