Robert Verkaik: Evidence mounts that practice was rampant

It was Mr Justice McKinnon, the judge at the Baha Mousa court martial, who first summed up the deepening sense of disquiet over the truth behind the abuse committed by British soldiers in Iraq.

He told the tribunal, which cleared six of the seven soldiers, that there had been "more or less obvious closing of ranks".

This week there were the first signs of a breaking of those same ranks when a former soldier told the public inquiry in London that he saw two of his comrades kicking and hitting Baha Mousa shortly before he died. Garry Reader told how, while then a private, he had tried in vain to resuscitate Mr Mousa in 2003. He said he had not told the truth previously, but did believe Cpl Donald Payne and Pte Aaron Cooper had caused Mr Mousa's death that September. Mr Reader said he had been afraid that speaking out would damage his career.

Mr Reader is by no means the only former soldier who has had an attack of conscience over the death of Mr Mousa. Another, Gareth Aspinall, told the inquiry last Monday he had seen Mr Mousa's body on a stretcher and heard Cpl Payne say: "If anyone asks, he banged his head." Cpl Payne, who remains the only soldier convicted in relation to the killing, will give his evidence on Monday.

Today we report that there are a further 33 cases of abuse for the Government to answer. They are alleged to have taken place in detention facilities across southern Iraq between 2003 and the British pull-out this year. Some of them include claims of sexual abuse which have echoes of the US-run prison camp at Abu Ghraib.

What is also unravelling is the Government's argument that there were only a few bad apples among the thousands of British soldiers who occupied Iraq. Ever since the allegations first emerged in 2003, the Ministry of Defence has denied that there has been any need to address a culture of abuse or indeed concede something terrible had gone wrong in the military handling of Iraqi prisoners.

As Rabinder Singh QC, counsel for Mr Mousa's family and other Iraqis detained with him, said at the outset of the Mousa inquiry: "This case is not just about beatings or a few bad apples. There is something rotten in the whole barrel."