“I don’t believe it was sexual assault. It was just drunken buffoonery by me.”Representing Cdr Heap, Lieutenant Commander Verity Fane-Bailey said: “Let’s make this a service issue, not a criminal one.””This has not taken place in a dark corner…he has not got a woman on her own in a corridor. It’s not hidden. The slap was hard, not a caress or a grope.”For the reasons I have outlined, I suggest you cannot be sure he sexually assaulted this woman.”After the panel returned its verdict, the judge told Bulford Military Court, Wilts, Cdr Heap, of Poole, Dorset, had been willing to admit a charge of ‘disgraceful conduct’ prior to the two day trial, but the prosecution were not willing to accept this. A court martial took less than an hour to clear a Royal Navy Commander of sexual assault after he begged them not to ruin his career over a “schoolboy prank”.Commander Steven Heap allegedly left a female colleague’s bottom sore after shocking her with two “firm slaps” during a Christmas party, in what he said was an “amusing not sexual” act of “drunken buffoonery”. The 48-year-old, who received an MBE from Prince Charles, told the hearing he was very drunk when he slapped her backside on the dance floor but insisted it was a “prank” and he was “showboating”.The panel of five senior male officers cleared Cdr Heap of two counts of sexual assault after 57 minutes of deliberations.Assistant Judge Advocate General Robert Hill said: “To convict him, you must be sure there was a sexual purpose to the slaps”.Prosecutors had alleged the Commander, who joined the Navy as a submariner 30 years ago, had been sexually motivated when he slapped the woman’s backside.However, Cdr Heap, who was based at HMS Excellent in Portsmouth, Hants, at the time, told the court he had been drunk and thought he was being “amusing”.He said: “I made a gesture, pointing to distract her and then slapped her on the bum. I thought it would be amusing, it was childish showboating, a ridiculous moment. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.