Two prison officers have been cleared of planting a homemade weapon in an inmate’s cell in revenge for a colleague being covered in excrement.

Peter Sutton and Gemma Whiteside were alleged to have taken the drastic action at HMP Swaleside on Sheppey as “payback” for the attack – known as potting.

But a jury acquitted Mr Sutton and Miss Whiteside of misconduct in a public office.

Maidstone Crown Court heard senior officer Mr Sutton was overheard by a civilian worker asking Miss Whiteside for the weapon.

Prosecutor James Fletcher said Mr Sutton, 58, vowed it would be found in Edward O’Neill’s laundry bag in his cell that day.

Miss Whiteside, 30, signed a report stating the weapon – a filed down comb with tape at one end to form a handle – had been found during a cell search.

Mr Fletcher said Mr Sutton and Miss Whiteside referred to the weapon as a pregnancy testing kit – a coded phrase which alerted occupational support group worker Jo Manning to their conversation.

She later reported the matter to the prison governor.

“It was an arrangement to make sure there was payback for the officer having had excrement thrown over him the previous day by the prisoner,” said Mr Fletcher.

When arrested, Mr Sutton and Miss Whiteside denied there was any conversation about a pregnancy testing kit or planting a weapon.