(WMC-TV) - Red light cameras should make driving safer, but those few seconds when the light turns yellow can make things even more dangerous when a camera is watching. The theory goes if drivers know they will get a ticket for running the light then they will not do it, but some people are getting caught in the so-called dilemma zone.
One driver suspects the City of Memphis may actually be shortening yellow lights to cash in on drivers caught in the zone.
"It's set up a circumstance where you're actually increasing the risk for a rear end collision," said Dr. Perry Rothrock who drives on Germantown Parkway during his daily commute.
He started paying close attention when red light cameras were installed at several major intersections
"It just seems that the yellow lights change too quick," he said. "I'm sure that there is some kind of standard of how long the yellow lights should last."
Rothrock suspects the city shortened the yellow lights to increase revenue.
The National Standard for a yellow light is anywhere between three and six seconds.
The Federal Highway Safety Administration recommends yellow lights last one second for every 10 miles per hour of the speed limit. If that were mandatory, the yellows in Rothrock's 50-mile-an hour zone would be five seconds. The lights are not that length.
"I think generally we set them at four seconds," said Memphis City Engineer John Cameron. "There are some 800 signals that we work with, so I won't say that there aren't any at three seconds."
Documents from Cameron's office obtained by the Action News Five Investigators show yellow lights at half the traffic cameras in Memphis are set at three seconds the other half at four seconds, which is certainly not the recommended five seconds on Germantown Parkway.
"It's a cynical ploy that is done to raise revenue at the expense of public safety," said John Bowman, with the National Motorists Association.
Bowman says shorter yellow lights create a dilemma zone where drivers are faced with a choice: rush the intersection and risk a ticket or accident or slam on the brakes and risk getting rear ended.
"People who are driving at faster speeds need more time to react and to stop safely," he said.
City Court Clerk Thomas Long collects the cash for the photo enforcement program, which has generated more than $2.7 million dollars in net revenue since 2009.
"If the citizen decides not to speed, not to run the red light, then there's no money," he said. "Believe it or not the traffic accidents they have decreased substantially."
The money is used to improve police technology and safety programs.
Long would not confirm whether or not the city is shortening yellow lights to make more money from drivers. He referred the Action News 5 Investigators back to the city engineer.
"We haven't, to my knowledge, made any adjustments to any of those signals that have the red light cameras on them," said Cameron.
Dr. Rothrock hopes that is true; he has had three traffic tickets that make him think otherwise.
"I think they're setting you up, if they're not giving you the appropriate amount of time," he said. "The government is supposedly here to serve us, and you would think that they would be more on our side instead of being ... A friend rather than a foe trying to obtain all the money that they can. They get plenty of it other places that's for sure."
Traffic cameras cost the city of Memphis $95,000 per month to operate. The city plans to add cameras at 30 additional intersections.
The city engineer's office is currently studying accident data from those intersections.
TDOT TRAFFIC CAMERA DESIGN MANUAL – Standards for timing of traffic lights: http://www.tdot.state.tn.us/Chief_Engineer/assistant_engineer_design/design/Traffic_Design_Manual.pdf
NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM – Study on Yellow Light Timing:
Copyright 2013 WMC-TV. All rights reserved.