A police firearms instructor has been fined £8,000 and ordered to pay another £8,000 in legal costs for shooting a Hersham man after failing to spot a Magnum 44 revolver was loaded.

Keith Tilbury, a police phone operator, was blasted back into his chair after being shot in the stomach at point-blank range during the classroom demonstration.

The bullet passed right through the body of the 51-year-old, who lay unconscious for 12 days after life-saving surgery on his bowel and kidney and was in hospital for another 10.

He has not worked since the incident on May 30, 2007, and probably never will, his solicitors have said.

His wife Joy, speaking at their home in Belgrave Close after the sentencing, said her husband still planned to go ahead with a civil lawsuit.

But she said Thames Valley police had acted honourably since the incident.

PC David Micklethwaite, 52, has since been moved to another police force and is still facing disciplinary action, Southwark Crown Court heard on Thursday during a prosecution brought by the Health and Safety Executive.

He was asked to conduct the training course at “short notice” and, after grabbing some ammunition from Quality Street tin in the police station the night before, he arranged the 11 civilian workers in a horseshoe around him and started to pull the trigger to show how the chamber spins on the Magnum.

Mr Tilbury, who used to shoot for the Berkshire county rifle team, realised pointing a gun at somebody was a breach of procedure and decided to move, but was not quick enough.

He told investigators: “I was not happy, because it was drilled into us to never, ever point a gun at someone. I was getting up to move from my chair when I heard two clicks and then a loud bang.”

The bullet passed through his body causing major internal injuries, hurling him backwards, and ended up in the arm of a wooden chair behind him.

Thames Valley Police, at whose headquarters in Kidlington, Oxfordshire, the shooting happened, was also ordered to pay £40,000 after the chief constable admitted breaching health and safety rules, plus another £25,000 in legal costs.

The Quality Street tin which the ammo was stored in had been used for several purposes, a subsequent investigation found, while other containers were also used for bullets, including a baby food tin.

But because of the haphazard storage, there was no way to tell whether the ammunition was live.

PC Micklethwaite failed a Metropolitan Police firearms certificate in 1995, which included aspects of safety, but others “were not made aware of his failing” when he was made a firearms instructor in 1999, the court was told.

Thames Valley Police considered the failing was to do with differences in procedure between the forces.

He was not at the court to hear his fine, but his solicitor apologised on his behalf for the shooting.

Summing up, Judge Nicholas Lorraine-Smith criticised Thames Valley Police for the “dangerous” way it stored ammunition and said: “it was a disaster waiting to happen”.

Thames Valley Police described the shooting as embarrassing and said it had now banned live ammunition from the classroom.

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