Playing red light, green light: Column

Jonathan Turley | USATODAY

It appears that politicians can see a yellow light when they need to. Facing a close runoff election and a ticked off electorate, Mayor Rahm Emanuel finally relented recently and promised to remove 50 red light cameras that made Chicago the country's largest speed trap. While citizens have complained for years, Emanuel only saw the light when polls showed he could lose re-election to a relative unknown. However, other (less endangered) politicians are still seeing rigged traffic lights as an easy revenue source.

Emanuel first gave Chicago the highest number of traffic cameras of any city, and then in February 2014 he allowed for tickets to be issued under yellow lights that lasted 2.9 seconds. After the practice was exposed by the Chicago Tribune, the mayor returned in September to the three-second minimum, which is set by federal law. But many drivers still complain it is not enough time at 30 miles per hour to get through intersections.

I experienced that fact firsthand when I returned to my hometown for Christmas and faced the patchwork of slow zones all over the city. At three seconds, the light turns red unless you speed to get across an intersection. Thus, if you try to cross the intersection, you can get nailed for both running the light and speeding.

Braking on yellow

I found myself hitting the brakes as soon as a yellow light appeared. I am not alone.

The Chicago Tribune found that these slow zones and yellow lights have resulted in 22% more rear-end crashes that caused injuries. (The study also found that the cameras reduced injury-causing "T-bone" crashes, or right-angle hits, by 15%.)

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Nevertheless, cities strapped for cash are turning to speed traps that were once ridiculed as a tactic of rural, small towns. About 500 towns and cities have installed red-light cameras, often through lucrative deals with private contractors. It is an irresistible temptation for many cities and their contractors (who receive a generous cut from fines) to rig the system to generate more revenue by posting speed reductions or shortening yellow lights, or both.

In 2013, Florida quietly reduced the timing of its yellow lights and generated more than $100 million in extra revenue. Likewise, a study of New Jersey intersections found that the contractor had shortened virtually every yellow light below the minimum timing to generate tickets.

The increased accidents in Chicago are consistent with academic studies. One study found that increasing yellow times by just half a second resulted in a decrease in accidents of up to 25%.

Most cities have yellow lights timed at 3.5 seconds. Maryland actually passed a law requiring at least 3.5 seconds; in Baltimore it is 3.6 seconds. Los Angeles and San Diego set their lights at 3.7 seconds and 3.9 seconds respectively. Philadelphia set its lights at four seconds to reduce the type of collisions now common in Chicago.

Devastating to families

This new revenue for cities can be devastating for families. A recent study showed that one in three Chicagoans has less than $250 in the bank every pay day. Yet Emanuel is handing out $35 tickets for six to 10 miles over the limit. If you go 11 mph over the limit, you are hit with a $100 ticket.

In Beverly Hills, one infamous speed trap hits drivers traveling downhill on Wilshire Boulevard with a short yellow light. The city just films car after car getting nailed and sends off a demand for payment. That yellow light, however, is still longer than Chicago's at 3.3 seconds vs. three seconds.

Ironically, standard contracts in some states give contractors a percentage of the fines — creating "perverse incentives."

Yet, these traps only succeed as windfalls for so long. In Chicago, while rear-end collisions are up, drivers are now avoiding intersections with red light cameras, and revenue from fines has dropped $50 million. New York City faced a similar shortfall.

That is, until these cities can come up with another way to trap their own citizens.

Jonathan Turley, a law professor at George Washington University, is a member of USA TODAY's Board of Contributors.

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