Rhodri Marsden: There's a lesson in Jack Straw for us all

For some reason the internet clouds our processes of reasoning

It doesn't rank as one of the most convincing scams ever perpetrated. Someone decides to send rambling emails posing as Jack Straw, Lord High Chancellor of Great Britain, with the story that he's lost his wallet in Nigeria and urgently needs $3,000 to get back home. The conman somehow figures that Straw's least likely course of action would be to call the British High Commission in Lagos; no, he'd send disjointed, pleading notes to his Blackburn constituents in the hope that they'd dig deep in their pockets and send him whatever they could afford via Western Union.

The scammers had no idea of Jack Straw's status; they just attempted to hack into a number of email accounts and struck lucky with his. It could equally have been yours, or mine, or Jeremy Clarkson's. But Straw wasn't really the intended victim; the recipients of the emails were. "Advance fee" fraud, which requests money on the promise of being handsomely rewarded at a later date, is incredibly common – and this particular email has been sprayed around the internet for last 18 months, featuring a range of remote destinations that the unlucky, non-existent traveller has found themselves in.

Straw, of course, hasn't been visiting Nigeria, and has maintained full command over the whereabouts of his wallet. But when the fake emails were opened over the weekend, people were sufficiently concerned to place calls to Straw's office to check that he was all right.

We all like to consider ourselves capable of sound judgement and logical thought, but for some reason the internet clouds our processes of reasoning. Whether it's because there are no established rules of online etiquette, or that we simply fear the technology we're using, we become credulous in the extreme. The email could have warned of Straw's plight after organising an unsuccessful badminton tournament in Uruguay, and someone would still send a reply saying, "Dear Jack, sorry to hear about the badminton, chin up, all the best, Jeff."

Straw's office could learn a thing or two about passwords from this incident: you might think that having, say, "lozenge" as a password would be fiendishly difficult for people guess, but if it's in the dictionary, you're not safe. However, acquiring internet savvy and becoming resistant to what's known as "social engineering" is far more difficult. So far this year, advance fee fraud has left a group of Canadian women out of pocket to the tune of $300,000 after being fleeced by fake Romeos on online dating sites, and a Canadian man lost $150,000 after being teased with the possibility of a huge inheritance. Canadians aren't particularly susceptible; we all are, if we don't stop and think.

Here are some rules of thumb that, deep down, you probably know: you can't make money fast online; there aren't dozens of attractive men and women in your local area desperate to have sex with you this evening. If puppies need adopting, their owners won't send you cute pictures and ask for cash. But if you do happen to fall victim to social engineering, remember that you're not alone.

People make honest mistakes, whether motivated by greed, or compassion. Thankfully, this particular fraudster made no money out of Blackburn residents; his mistake, of course, was to imagine that they'd feel much compassion for a penniless Jack Straw.

r.marsden@independent.co.uk