Defence Secretary Philip Hammond told ITV News it was not for him to judge whether Sgt Danny Nightingale should have been sent to prison.
He added that the Court of Appeal "acted swiftly" in this case which showed the system was "robust".
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After a cold start, it will be a mostly bright and sunny Sunday for many of us with temperatures way above the norm for the time of year.
In a wide-ranging Peston on Sunday interview, he said Parliament security needs reviewing and the PM's counter-terror strategy is flawed.
The star celebrated his 70th birthday with his family before attending a celebrity-filled bash held in his honour.