Why are police sketches so bad?

Remember when everyone looked like the Unabomber?

I was at the gym the other day (no joke) when the police sketch of a robbery suspect came on the TV. He looked like a very pretty woman wearing a hijab. He was supposed to be a crook in a hoodie. I nearly tripped on the elliptical.

It reminded me of the sketch earlier this year of a Kings Island sexual assault suspect:

I was on the lookout for an especially hirsute lady until I realized this was supposed to be a drawing of a dude. Last I heard, this case was unsolved. The mustachioed women of Mason must have gone into hiding.

I once helped put together a police composite after an acquaintance and I were jumped on the University of Missouri campus (likely a rival journalism gang), and I remember sitting there choosing eyebrows and noses and wrinkles until the face resembled a real one. Was it one of the guys who beat up my friend? No idea. They never caught the men. Which makes me wonder — just how useful are police sketches, anyway?

Here’s a quote from a Philadelphia Inquirer story at Physorg.com story on the matter.

Charlie Frowd, a British researcher who has studied techniques for improving composites, said a good way to evaluate them is to see whether they can be correctly identified by someone who already knows the subject of the sketch.

By that standard, laboratory studies have found that the worst accuracy is achieved by computer programs that ask the witness to pick out features one by one, said Frowd, a University of Central Lancashire psychologist. It depends on how soon the witness is asked to recall a face, but when they wait a day or two, as often happens in a real-world investigation, these computer composites are recognizable just 5 percent of the time, he said.

Composites by human sketch artists get better results, achieving about 9 percent accuracy, Frowd said.

OK, to be fair — sometimes sketches work. They even resemble the people they’re supposed to be.

But so often, all they do is make us laugh. Let’s look at some anecdotal evidence. You don’t have to do much searching to find websites like this, which show how some police sketches — most of them human-generated — don’t look like people at all. And surely we have not forgotten about this gem, a suspect in the abduction of a 75-year-old woman from a Crestview Hills mall parking lot?

Yes, this post was just an excuse to feature the best police sketch of 2011.

Let’s hope the future brings better police sketches — or at least better than these of the mashed potato-faced Hamilton County rape/robbery suspect who looks like every guy I’ve ever seen sitting at the bar at Nicholson’s. (They caught this guy, by the way. See if he matches.)


2 Replies to “Why are police sketches so bad?”

  1. Hilarious… I am crying a little. Lori are considering a career as a police sketch artist. Your images are waaaayyy better than these.

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