Rhodri Marsden: I've spent 40 years not being naughty and I'm now terrible at lying

Ever since childhood I've been terrified of the consequences of disobedience and prone to sickeningly obsequious behaviour around figures of authority, eg anyone with a uniform, a double-barrelled name or a horsewhip. As a boy I'd say things like, "I don't think we should be doing this" or "what if someone sees us?" while my friends gleefully urinated up the side of Dunstable Leisure Centre and then wrote ULTRAVOX on it in chalk.

I've now spent 40 years adhering strictly to regulations and the only time I found myself in a police cell – having my bum probed for class A drugs by a Belgian border guard – I could proudly allow him to perform his duties in the knowledge that my arse has always been squeaky clean.

But the trouble with this lifelong commitment to not being naughty – aside from me being a tedious, moralising presence during stag weekends in Latvia – is the anxiety I experience when I'm being less than truthful. I exhibit all the classic signs of dishonesty – crossing my arms, looking at the ceiling, saying "please don't pay attention to these classic signs of dishonesty" – and if I were ever wired up to a lie-detector machine it would probably start laughing, you know, like those robots used to in the instant-mashed-potato adverts.

Anyway, I was in Starbucks last week, and as per the new company policy I was asked for my name at the counter so they could scribble it on the cup. But I didn't say "Rhodri" because I couldn't be bothered to enunciate it three times and then spell it, so I found myself saying "Peter?" with a strange upward inflexion. This not only indicated that I wasn't actually Peter, but also that I was unhappy with the nom de café I'd just chosen. I felt ridiculously uneasy at having given false ID to a barista. She clearly knew that I was fraudulently purchasing a cappuccino for Peter and I was going to pretend to be Peter to get it.

So when the coffee arrived I decided to come clean; I explained that it was my coffee but my name wasn't actually Peter. She shrugged. I know this story pales in comparison to the one about George Washington and the cherry tree, but hey, it's not like I'm trying to be the first President of the United States.

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