Sophie Morris: Men have such suspicious minds

There's only one reason why the guys identifed more cheaters

I haven't the first clue why the results of new research into infidelity are being held up as evidence than men are better at spotting a cheating partner than women. Not at all. It simply shows us that men are more suspicious of their lovers than women are of theirs. Why? Well I guess it takes one to know one.

Ouch. Is this unfair? I'm only analysing the findings of this investigation with a slightly more critical eye than Paul Andrews, the academic who conducted the research at a US university. It turns out that nearly twice as many of the men questioned as women had been unfaithful. They modelled their answers about their partners' behaviour on what they know about their own.

More than 200 young heterosexual couples answered the confidential questionnaires about whether they suspected or knew that their partner was playing away, and 80 per cent of women guessed correctly. A high number in itself, which rather undermines all that Mars and Venus folklore and suggests that on the whole people know their partners pretty well. This is a nourishing thought, or would be were we traversing a more heart-warming topic than infidelity.

But the men, a whopping 94 per cent of them, knew exactly at which point their missus was actually "working late" and when she was taking a liberty with their trust, and possibly their best friend. The reason, though, they scored better is because they erred heavily on the side of distrust. This meant the men detected 75 per cent of cheating women, while the women only caught out 41 per cent of their wandering men. It doesn't take a sleuth to work out that the men also suspected infidelity where there was none.

In fact, the only reason the guys identified more cheaters is because they suspected more in the first place. If you don't trust anyone, then when you catch your partner in flagrante you should not be surprised, but gleefully vindicated in your paranoid distrust.

So we have learnt that men exist in a suspicious bubble, constantly asking which "friend" you saw and wondering whose texts are making you giggle. It can't be very cosy with your neck always craned to see if she is dialling some other, presumably hotter property. I'm not suggesting you drop your guard entirely and surrender yourself to a woman's guile – doe-eyed puppies do tend to get kicked about a bit – just quit skulking about like Columbo.

Or we could take the approach of another US academic, one David Buss, who has gleaned from these results not that men are fearful paranoiacs. No, he has discovered a, "fascinating cognitive bias that leads men to err on the side of caution by overestimating a partner's infidelity". But, you see, or rather Buss does: men have more reason to be hung up on infidelity, given they have much more to lose. Oh yes – they face the possible ignominy of spending a lifetime bringing up another man's child, and forfeit their own chances of producing a son and heir.

And if that's not enough to have you reaching for the Kleenex and vowing never, ever to sleep with anyone else until you've had his three children and he's left you for someone else, get this: Andrews, Buss et al have decided that women probably do cheat as much as men after all, but they lied to the researchers to cover their tracks.

This is probably the right moment to point out that this is contemporary research, and should not be confused with the Salem witch trials of the 17th century.

s.morris@independent.co.uk