Thats funny you mention that....
Think about this, most lights have sensors at the fat-white-line and communicate w/ the light controller. But, there are also smaller sensors a few hundred yards before the light itself...
Now, what if, the companys and counties with the photoenforcement have it set to trigger the light to change to red when you go over the first sensor, undoubtably getting more photoenforced tickets from people trying to beat the light.
I would be curious to see, when there is little to no traffic, if this lights actually did this...
