“So whilst British service personnel knew when to shoot under rules of engagement they received no guidance on what to do when arresting, detaining or interrogating someone.

“In the aftermath of Iraq, our servicemen and women have been hung out to dry. It must stop.”

Ms Meredith said the MoD must guarantee welfare and medical support for both serving and former personnel and help from the chain of command.

She said she was also calling for the right to funded and independent legal advice, the right to a fair trial and for time limits to be imposed on cases.

She said there were also concerns about the conduct of the investigators. Gen Sir Nick Carter, the head of the Army, has said his soldiers are innocent until proven guilty and demanded they are treated with respect.

In addition to IHAT, a separate inquiry, Operation Northmoor, is looking at more than 550 allegations of abuse in Afghanistan dating back to 2005.

Johnny Mercer MP, chairman of a Parliamentary inquiry into the treatment of troops under investigation, said IHAT had been a “spectacular failure”

He said: “It has failed to complete its core function of prosecuting those who have broken the law; it has taken a devastating toll in the - at times unlawful - pursuit of those who have done no wrong; and it is an appalling waste of public money.”