I love the bumper sticker question in voir dire. I've met lawyers and seen journalists who are surprised by it, or think it's intrusive, but when you think about it, it's a no-brainer. If a juror holds an attitude so strongly that she'll paste it onto her car, you want to know what that attitude is.

New research suggests you should be interested in something else, too. It isn't simply what jurors' bumper stickers say, it's whether jurors have bumper stickers at all. Writing in the June issue of the Journal of Applied Social Psychology, Colorado State University researchers suggest that people with bumper stickers are more likely to be aggressive and angry people, or at least aggressive and angry drivers.

Visualize THIS.

I haven't found a free version of the paper on line, but the Washington Post picked up the story (thanks to the Situationist for flagging this) and describes the research this way:

[Lead author William] Szlemko and his colleagues at Fort Collins found that people who personalize their cars acknowledge that they are aggressive drivers, but usually do not realize that they are reporting much higher levels of aggression than people whose cars do not have visible markers on their vehicles.

Drivers who do not personalize their cars get angry, too, Szlemko and his colleagues concluded in a paper they recently published in the Journal of Applied Social Psychology, but they don't act out their anger. They fume, mentally call the other driver a jerk, and move on.

"The more markers a car has, the more aggressively the person tends to drive when provoked," Szlemko said. "Just the presence of territory markers predicts the tendency to be an aggressive driver."

The amazing thing is that the aggression didn't change with the sticker's message. Drivers who chose peaceful messages like "Visualize World Peace" were just as obnoxious on the road as those who slapped "My Kid Beat Up Your Honor Student" on their bumpers.

My car, my street, my interstate highway

Those two drivers would call themselves each other's opposites, but they have an important trait in common: a strong and confused sense of territoriality. The Post article continues:

The key to the phenomenon apparently lies in the idea of territoriality. Drivers with road rage tend to think of public streets and highways as "my street" and "my lane" -- in other words, they think they "own the road."

* * *

Drivers who individualize their cars using bumper stickers, window decals and personalized license plates, the researchers hypothesized, see their cars in the same way as they see their homes and bedrooms -- as deeply personal space, or primary territory. . . ."If you are in a vehicle that you identify as a primary territory, you would defend that against other people whom you perceive as being disrespectful of your space," Bell added. "What you ignore is that you are on a public roadway -- you lose sight of the fact you are in a public area and you don't own the road."

Issues of anger, territoriality, and boundaries are critical in all kinds of trials. If they're critical in yours, think a little longer before you keep -- or strike -- that nice lady with the "Coexist" bumper sticker.

(Photo by Hadi-helvetIQ at http://www.flickr.com/photos/23081931@N02/2490169298/; license details there.)