We’ve all done it. Played the "I’m a lawyer" card, that is. Well, all of us who can claim to be lawyers, at least. Maybe individuals such as Peter Foster, the well-known conman and governmental confidante, have pretended to be lawyers in times of acute stress, or when a confidence trick requires such boldness, but for present purposes let us confine ourselves to the deadly act of hubris implicit in the words "I am a lawyer," as uttered by those who actually are.

The act of saying "I am a lawyer" rarely has anything but a negative effect. People will say that the reason for this is obvious. Lawyers are unpopular, because they are seen as meretricious, and so naturally no one will applaud them when they reveal themselves unlike, say, a doctor who strides to the scene of an accident saying "Let me through, I am a doctor" (one can imagine the reaction of a crowd to a personal injury lawyer announcing his profession in the same situation). But there is something else at work, too, as the following tale of life at 30,000ft will illustrate.

A couple from California found that they could not contain their affection for each other during a flight from Los Angeles to Arizona. Carl Warren Persing and Dawn Elizabeth Sewell’s apparent eagerness to join the Mile High Club did not, however, go down well with their fellow passengers, who soon began to feel "uncomfortable". No wonder, for as well as "kissing and snuggling" Mr Persing appears to have decided that the best location for his head was in his girlfriend’s lap.

All good media lawyers will recall that Gillian Taylforth made a similar decision with regard to her partner, Geoff Knights, nearly 15 years ago on a slip road of the A1. Unfortunately for her, the police witnessed something that convinced them that a sexual act was taking place. In vain did Ms Taylforth protest that she was attending to her partner’s upset stomach, and Gorgeous George Carman, a man who never had to say "I am a lawyer" because everyone knew that he was, had a wonderful time casting further doubt on this excuse come the actress’s day in the libel courts. Ms Taylforth duly failed in her 1994 libel action against The Sun, which had claimed that she was performing oral sex on Mr Knights in his Range Rover.

Mr Persing and Ms Sewell also find themselves heading to court. The pair have been indicted and charged with violating the Patriot Act, legislation introduced to deal with terrorist acts, because rather than cease their sexual shenanigans they allegedly continued and then threatened the flight attendant who had the temerity to ask them to stop. When he refused to serve them any further alcohol, Mr Persing appears to have upped the ante with a threat that he may now regret: "You and I are going to have some serious confrontation when we get off this plane."

The amorous duo is set to stand trial on December 11 at the federal courthouse in Wilmington, California. Mr Persing’s lawyer says his client’s head was in his girlfriend’s lap because he was feeling sick, and this, as well as the issue of whether allegedly "overt" sexual behaviour constitutes the intimidation of aircraft personnel such that they are prevented from carrying out their duties, is one of the issues before the court. The court will also, however, have to consider some dread words uttered by Ms Sewell.

"I work for a lawyer," she is reported to have said, capping this with a no doubt reasoned exposition of why it was "illegal" for the flight attendant to stop serving her and her man alcohol.

Ms Sewell did not say "I am a lawyer" but of all her alleged crimes, I would wager that the straw that broke the camel’s back was this statement. There is little so infuriating as a lawyer – or someone purporting to have legal knowledge – brandishing their skills outside the office or courtroom. The trouble is, we’ve all done it. Not try and join the Mile High Club, but appear as arrogant fools merely because we think we possess a set of skills that distinguish us from mere "laypeople".

In a better world, lawyers would be even more discreet than those who have successfully – without legal liability - joined the Mile High Club.

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