Memo to those still pushing for red-light cameras in Fort Wayne (or pushing for the state to let us do it): Let's keep researching the evidence, OK?
A U.S. House Subcommittee on District of Columbia Appropriations grilled Washington, DC Mayor Anthony Williams over his lucrative red light camera and speed camera program on April 6. To date, the system has issued $177 million worth of citations, but one member of Congress is questioning the evidence that the devices have done anything to improve safety.
"Virginia did a study," said Congressman Todd Tiahrt (R-Kansas). "They found that -- in the intersections where they had them, they noticed there was an increase in rear-end accidents. People panic, and when they see the camera, they notice it at the box up there and they put on the brakes and rear-end accidents (happen)."
Comments
I have looked into traffic lights from an engineering standpoint. My interest was solely in determining the amount of time a light should stay yellow.
For example a car traveling at 30 miles per hour is actually traveling 44 ft per second. The average reaction time is about 1/2 second. This means the car will travel 22 feet before the average person begins to react. If the intersection is 50 feet wide, then the light needs to stay yellow for at least 1.1 seconds. Add in the reaction time and you are at 1.6 seconds. But wait, you need time to break and come to a stop. My question has always been, what is the design criteria for deceleration? Do you come to stop normally which could be anywhere from 2 to 4 seconds? Stomp on the breaks? I have been unable to find any definitive tables identifying the deceleration rate for cars or trucks. With said, how do they determine how long a yellow light stays yellow?
Until this is known, standardized and published to the people, I think cameras are wrong.
How fast should people brake? What is the expected time to react? You have to judge how far you are from the intersection, take your speed into account and calculate if it is safe to stop (not get rear-ended) or proceed.
The statistic about rear-enders makes sense to me. I seem to read more often about elderly folks getting rear ended, and you'll often see foreign college students driving cars with mashed trunks. I speculate that is because these folks' driving may be more timid in general.
Cameras appear to introduce an extra man-made element of genuine fear for the innocent as well as the lawbreakers (tickets = points = insurance trouble = big bucks) which no doubt will result in unpredictable behavior and a lot of unnecessary brake-squealing, emergency stops by perfectly good people who think their behavior is defensive driving.
One may well ask -- defensive for whom? For the family who gets rear-ended? For the family who couldn't stop as short? For those in the chain reaction behind? For those in the traffic jam while the accident waits to be cleared? Common sense says there's nothing defensive about a sudden stop rising from nothing more than a clutch of panic over a moving violation.
If cameras become the norm, we may well have to adjust the legal assumption about the driver in back always being at fault for an accident. If you really can't help rear-ending someone who is driving badly enough to endanger others where no true emergency exists, it can't automatically be the ambushed follower's fault any more.
Since the brakes on various cars and trucks have different stopping distances even when new, contests between the binder-clampers and everybody behind them will come down to who owns the more efficient braking system. Woe be it unto the heavier vehicle behind the lightweight with the four-wheel discs.
As I understand it, these cameras would be time delayed so as not to catch the majority of us, but only those who blatantly run red lights from the straight or turn lanes. I hope that will be true, and that the fact is well known, so that those tempted to freak out on yellow will have the confidence to finish what they have started.
Which reminds me -- it's not illegal for one or two cars to enter an intersection on green while waiting for a break in traffic to complete a left turn. If traffic coming from the opposite direction doesn't slow and stop soon enough, cars in the intersection often won't be allowed to complete their turns during the yellow light.
I would not like to see these cars cited for clearing the intersection on red, since no law has been broken, and there are some places without a green arrow where a left turn would seldom be possible otherwise.