May 18, 2012 > Letter to the Editor: How to trap motorists: Red light cameras and short yellow lights
Letter to the Editor: How to trap motorists: Red light cameras and short yellow lights
Before a city can issue a red light camera ticket, it must make sure that the yellow light interval meets the minimum state standard. Here is how to legally shorten a yellow light in order to issue more camera tickets.
On Mowry Avenue at Farwell Drive in Fremont there is a red light camera. This camera captures more straight through violations than any other camera in Fremont due, in part, because it is a heavily traveled road but mostly because of the shortened yellow light. Here is how this yellow light has been shortened.
There are two main variables in the formula to determine minimum yellow light time. The formula uses the average perception/reaction time of drivers and speed of traffic. Now, the speed of traffic can either be the actual speed measured in the latest engineering survey or the speed limit of the roadway. Mowry Avenue's critical speed of traffic is 45.4 mph, but the speed limit has been lowered to 40 mph. Fremont, in determining the length of the yellow light, chose to use the speed limit. Thus, the minimum yellow light time is calculated at 3.9 seconds. Fremont's policy is use that minimum and round up to the next 1/2 second interval, thus the yellow light time is 4.0 seconds. This is all legal.
If, however, Fremont actually recognized that faster traffic needs greater stopping time and distance and it used the critical speed of 45.4 mph in the formula, it would yield a yellow light time of 4.3 seconds or rounded up to 4.5 seconds.
No Big Deal. Right? What is the impact of that 1/2 second? Studies of other camera locations show that when the yellow light is at the minimum, that 40-60% of violations occur in that first 1/2 second after the light turns red. A check of the actual ticket counts at Mowry and Farwell shows 2,017 tickets were issued in the last 12 months placing it firmly in first place among all 10 cameras as the busiest camera for citing straight through violations... over twice the average. Now if Fremont acknowledged that faster traffic needs greater stopping time and distance, and used the just the minimum for actual speed of traffic, there would be there would be 800-1,200 fewer tickets.
So, an extra 70-100 people are cited each month. Not a big deal. Just a little trickery, and, so what, there are plenty of other drivers who have time to stop. But, those citations yield around $130,000 per year in increased revenue to Fremont. This amount coupled with the extra income derived from a similarly shortened yellow at Decoto Road and Paseo Padre Parkway takes the camera program from being a potential loss into the profit column.