One of the biggest investigations into the alleged abuse of teenage Army recruits in Britain has collapsed.
Sixteen instructors at the Army Foundation College, Harrogate, North Yorkshire, were accused of slapping and punching 28 recruits.
A judge branded the three-year Royal Military Police (RMP) probe “seriously flawed” as he halted the first of three courts martial.
There are now calls for senior RMP officers to be investigated.
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The investigation had considered complaints from a total of 40 recruits about 30 instructors – which led to the prosecution of 16 of them, all sergeants and corporals.
The allegations centred on how recruits, aged 16 and 17, were treated at training camp in Scotland in the summer of 2014.
Recruits claimed they were slapped or punched in the face, spat at, grabbed by the throat, had their faces submerged in mud or were ordered to eat animal manure.
However, it took two years to interview the soldiers involved under caution and another year before they were told they were being charged.
In addition, handwritten accounts made by some recruits shortly after the alleged abuse have never been found and the military court heard some recruits claim they were threatened into giving statements and to appear as witnesses.
The courts martial at Bulford, Wiltshire, collapsed after eight days when the prosecution offered no evidence in 24 of the 31 charges faced by the first 10 defendants.
Five were cleared and Assistant Judge Advocate General Alan Large halted proceedings against the remaining five, ruling they could not get a fair trial.
The prosecution indicated it would offer no evidence against a further six instructors due to go on trial next month.
It emerged the RMP officer leading the investigation, Capt Teresa Spanton, did not question eyewitnesses because she thought they would lie.
“The decision not to interview, at any stage during a very long inquiry, such highly relevant eyewitnesses is a very serious breach of the duty upon police officers to investigate a case fairly and objectively,” the judge said.
He said her assumptions were “frankly startling”.
“It reflects a totally blinkered approach to the police’s duty of establishing, fairly and objectively, what happened,” he added.