Sergeant Danny Nightingale will try to clear his name at an appeal against his conviction today.
The SAS sniper was jailed for 18 months in November for illegally possessing a pistol, but released three weeks later after appealing his sentence.
At the time, Sgt Nightingale, from Crewe, Cheshire, vowed to clear his name.
His appeal will be heard at the Royal Courts of Justice in London.
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