Profiling

One of the frequently heard arguments against profiling is that there are exceptions which the profile won't catch. Thus, when we point out the stupidity of conducting anti-terrorist searches purely at random, and wasting time searching grandmothers from Iowa instead of concentrating on those who appear to fit the profile of Islamist terrorists, we're sure to hear the refrain "what about Timothy McVeigh and Richard Reid". Now, via Michael Totten at Instapundit, comes this version of the same argument, making the point that not all radical Islamists look the same. If you're stopping people strictly according to a profile, Yvonne Ridley could probably pass, at least if she would take off her head scarf.

Well, yeah. As any fule kno, profiling, even the very best available, isn't 100% reliable, and can't be, ever. There will always be someone who doesn't fit the profile, and thus stands a better chance of avoiding detection - and who will never be caught at all, if everyone always searches according to the profile. That's why the DC snipers avoided detection for so long; everyone was looking for a white loner, because that's who usually does this sort of crime, so the two black guys went right on shooting until someone looked outside the box.

And that's why I've yet to hear anyone argue that police should stick exclusively to a narrow profile, and never stop anyone outside it. Every description I've ever seen of how profiling works, includes some random factor which changes regularly, precisely in order not to give a free pass to the unusual criminal or terrorist. For instance, a particular guard might decide, in addition to the usual criteria, to stop anyone who is wearing a particular colour, and change that colour every hour. Or she might, every 5 minutes, stop someone completely at random. But most of the time, she should concentrate on the profile, and anyone who does fit it should come in for extra scrutiny.

Because, let's face it, the Ridleys and Reids of the Islamist world are the exception, not the rule. Given an unlimited supply of volunteers, the terrorist leaders might concentrate on sending only atypical-looking people out on missions, but they don't have an unlimited supply of volunteers. They've got a handful of white converts, and a whole lot more Middle-Eastern or Asian Moslems from birth. And the few whites make up a tiny percentage of all the white people who pass through a checkpoint, while the terrorists who fit the profile make up a far larger (though still quite small) percentage of all the people who look like them and who pass through the checkpoint. And there's nothing anyone can do about that.

Now a word about the people who do fit the profile, and who are therefore singled out for special scrutiny. No, it isn't fair on them. And the people who do the scrutinising have to bear in mind that the overwhelming majority of the people they stop will in fact have nothing to do with terrorism. So they have to be extra careful to treat them with courtesy, and, having found nothing wrong with them, to apologise for the inconvenience. But none of this makes profiling a wrong or immoral policy.

Here's a f'rinstance: it is a regular practise for the authorities to issue pictures of wanted people. Sometimes these are photographs, so they're by definition fairly accurate; sometimes they're photofit drawings, and are, to put it mildly, less accurate. But no matter how accurate one of these pictures is, there are going to be quite a few people who bear a strong resemblance to the wanted person. Perhaps they are relatives - perhaps even identical twin siblings - or perhaps they have no known connection, but happen to look like them. Suppose there are 10 people who look like a wanted person; that means that when the police stop someone on the basis of the picture, there is a 91% chance that the person is completely innocent. They should certainly bear that in mind, and not immediately knock the person to the ground or slap handcuffs on them. But should they refrain from stopping them and asking some very pointed questions? Of course not. If you happen to be one of those people who look very like a wanted criminal, life will get very tiresome until the criminal is caught. But that's life, and it's absurd to suggest that the police should solve your problem by stopping people at random, even if they look nothing like the criminal.