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Alleged ‘Excessive Force’ Incident a Case Study in Cognitive Bias

Picture this in your mind:

On a cool evening in late October, a man driving a crew-cab pickup with roll bars in the bed pulls into the parking lot of an upscale grocery store in Santa Barbara. The man exits his pickup and locks it, then walks quickly toward the sliding glass doorway of the store. From a few yards away, a policeman yells out, ordering the man to step back into the car. The cop is young and relatively new on the force.

He will report later that he had been trailing the pickup for some miles. It had been swerving erratically, he will claim, and he had tried to initiate a stop on the street near the entrance to the grocery store lot. Court and police records — which may have been available to the officer on his laptop at the time — show that the truck’s owner has a history of DUI-related charges, and is driving on a suspended license.

The man does not return to his car, but continues walking away. The officer steps forward and grabs his arm. According to reports issued the next day by police, the driver at this point breaks free, forcing the officer to grab, trip, strike and knee him several times around the face and body. A Taser is also used against the man.

Bystanders in the parking lot are startled enough to stop and watch. According to one of them interviewed later by a reporter, at some point in the struggle, the man shouts, “Why are you doing this?” The officer shouts several times, “Stop resisting arrest.” Other officers arrive, and the pickup owner is arrested.

Several hours later he is photographed with bruises and contusions on his face, several broken ribs and a broken nose. The man will make a statement after his release denying he resisted arrest. “I laid down like a lamb,” he said. The police have taken blood to test alcohol levels, though the man says he had consumed exactly one drink on the day of the encounter.

Now answer this: Are we looking at the use of excessive force here, or simply an unruly citizen being arrested with forceful but legal methods?

It’s a pretty good story. It’s got a good guy, a bad guy and a cliffhanger ending. Depending on your view of these things, the bad guy is either the policeman or the pickup driver, and true justice hangs on the fate of an unreleased police video.

But it doesn’t matter what the video ultimately shows. As Daniel Kahneman argues in his new book, Thinking, Fast and Slow, “facts that challenge basic assumptions — and thereby threaten people’s livelihood and self-esteem — are simply not absorbed.” Basically, our cognitive biases are more likely to change our interpretations of events than events are to change the way we see things.

This means:

Your preconceptions about the arrest at Gelson’s will most likely dictate your understanding of the video (if you ever get to see it) rather than the reverse. You will view the video through the lens of your apriori opinion of the case, and guess what? It will be obvious that you were right all along! And even if (like me) you weren’t quite ready to make up your mind, well, after watching the film, you still won’t be able to.

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