The ex-investigator said most soldiers served their country with dignity
The Royal Military Police has failed to investigate claims of abuse against civilians by British troops in Iraq and Afghanistan, a whistleblower has said.
The former senior investigator said the RMP was not equipped to deal with the pressures of their own investigations.
He told BBC 5 Live's Donal MacIntyre programme allegations of torture and murder were being "covered up".
The Ministry of Defence said there was no evidence of failures and claims of abuse were always fully investigated.
Speaking anonymously, "John" said whilst most British troops had served their country with distinction, hundreds of suspicious incidents of alleged misconduct had not been properly investigated or simply ignored.
Referring to his time in the RMP's Special Investigation Branch, he said: "I believe that I was serving in something that was party to covering up quite serious allegations of torture and murder.
"... For too long I belonged to an organisation that wasn't seeking out the truth."
He said a lack of resources was partly to blame, but claimed there were also serious structural flaws in the Army justice system.
One case which came to his attention involved the alleged murder of an Iraqi by a British sergeant.
There was, he claimed, evidence to strongly suggest the Iraqi victim had been shot at point blank range for throwing rocks at a British Army tank.
He told the BBC: "A friend of mine who was a senior NCO went to the scene and was ordered not to investigate it as a murder. He was told that statements should just be taken as if it was a routine incident."
Some cases involving allegations of murder and abuse, followed by a failure to carry out an adequate investigation, have already come to public attention.
The death of Baha Mousa, an Iraqi hotel receptionist who died in British military custody having allegedly been beaten by soldiers, is currently the subject of a public inquiry.
Responding to the allegations, the MoD insisted any substantive allegations of abuse brought to its attention would always be investigated as fully as possible and that such cases were relatively rare.
It also said there was no evidence of systemic failure or interference in the RMP or military justice system.
In a statement it added: "We must remember that over 100,000 of our personnel served in Iraq and, with the exception of a few individuals, they have performed to the highest standards under extraordinarily testing conditions there."
You can hear the full report on the Donal MacIntyre programme on 5 live on Sunday, 11 October, 2009 at 1930 BST. Download the free
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