`Moth Effect'- Cause Of Roadside Accidents?

Gawkers.

Rubberneckers.

Call 'em what you will, they're a major irritant, those people who slow at accident scenes, glance at the carnage and cause traffic to back up.

``Human nature'' has been my best, awkwardly offered explanation of why that occurs.

But now I know another answer: The moth effect.

Yep. People are like little insects. Show 'em a bright light and they come flocking. So says a 114-page report sponsored by the AAA Foundation for Traffic Safety with the imposing title, ``A Search for Evidence of the Fascination Phenomenon in Road Side Accidents.''

It was done by three researchers, including John Crank, a political-science Ph.D at Washington State University. It's largely based on data from California, Kentucky and Illinois, including 101,890 Illinois accident reports that showed 172 legally parked cars a day are hit there. Nationwide, 200 people a year are killed when struck at accident scenes.

The phenomenon has various names, including the moth effect, fascination and target fixation; in a way, it's one of those things that seems based on common sense - police cars, after all, often have attention-getting rotating lights turned on, so it's not surprising people look.

Turns out life might be safer if police cars didn't have all those bright lights.

For example, the Illinois State Police studied accidents involving their troopers and found officers driving cars without roof lights ``were involved in 65 percent fewer accidents per million vehicle miles.''

The study also found patrol cars with exterior red lights were involved in fully 40 percent of all the Illinois State Police accidents, for a variety of reasons, but including the inherently dangerous situations where the lights were used, and a false sense of security provided by the lights.

In fact, the report noted, the reasons for the lights are based on somewhat contradictory factors. ``First, officers want to draw attention to themselves when they are in law-enforcement situations. . . . Second, it is widely believed that blinking lights will deter passing traffic away.''

I see. Sort of like lighting a bonfire in your front yard doesn't make people come to your house.

Still, among the report's conclusions were findings that emergency vehicles are not disproportionately involved in such accidents; that most roadside accidents take place in good weather on straight highways; alcohol and fatigue usually aren't involved; single-unit trucks, vans and pickups were disproportionately involved as the striking (moving) vehicle, and that driver inattention plays a major role.

Finally, the report decided that ``no solid evidence was found'' to support conclusions the moth effect does or does not exist - but the report also noted that in 1987 both Illinois and California removed all external light bars from patrol cars.

You can get the whole report by writing to the AAA Foundation for Traffic Safety, 1730 M Street N.W., Suite 401, Washington, D.C. 20036.