...reading some years back that the Red Light camera companies had specific language in the contracts that restricted the length of yellow lights.

A cynical person might think they wanted people running red lights. But I'm not...oh, fuck it. I am cynical.

In many states drivers are taught to enter the intersection to take a left turn, and it's legal.

specifies that the duration of the yellow change interval should be between 3 and 6 seconds. And people have won court cases over red light tickets over the yellow time being too short.

http://www.ite.org/decade/pubs/IR-117-E.pdf [ite.org]

http://www.ite.org/safety/issuebriefs/Traffic%20Signals%20Issue%20Brief.pdf [ite.org]

http://www.ite.org/annualmeeting/compendium10/pdf/AB10H2601.pdf [ite.org]

"Oh no, the light is now red, there is intersecting traffic"

no cross traffic should enter the intersection until the way is clear.

Green != Go

Green = precede if clear

Was it Washington, DC?

Source [washingtonpost.com]

The [Washington] Post obtained a D.C. database generated from accident reports filed by police. The data covered the entire city, including the 37 intersections where cameras were installed in 1999 and 2000.

The analysis shows that the number of crashes at locations with cameras more than doubled, from 365 collisions in 1998 to 755 [in 2004]. Injury and fatal crashes climbed 81 percent, from 144 such wrecks to 262. Broadside crashes, also known as right-angle or T-bone collisions, rose 30 percent, from 81 to 106 during that time frame.
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The results were similar or worse than figures at intersections that have traffic signals but no cameras. The number of overall crashes at those 1,520 locations increased 64 percent; injury and fatal crashes rose 54 percent; and broadside collisions rose 17 percent.

Overall, total crashes in the city rose 61 percent, from 11,333 in 1998 to 18,250 last year.

Also worth reading this - Oregon DOT Recommendations: http://www.oregon.gov/ODOT/HWY/TRAFFIC-ROADWAY/docs/pdf/ODOT_yellow_red_clear_policy_A1.pdf?ga=t

The 3 to 6 recommendation is based on some general assumptions and characteristics. It's still a mathematical equation. Also, here's a few c/p from the parent's references that are relevant (including the statement that yellow duration is commonly limited by control manufacturers and the shortfall is made up during a red phase):

The calculation requires values for perception/reaction time of the driver, deceleration rate for stopping vehicle, vehicle speed, approach grade (uphill, downhill), intersection width and design vehicle length. The standard value used for the perception and reaction time of drivers approaching a signalized intersection is 1.0 sec.

The Highway Design Handbook for Older Drivers and Pedestrians concludes that the 1.0-sec. reaction time is appropriate for both older and younger drivers, but that the use of a 1.5-sec. reaction time “is well justified when engineering judgment determines a special need to take older drivers’ diminished capabilities into account.”

The MUTCD (Manual of Uniform Traffic Control Devices) indicates that the yellow change interval should be set within the range of 3 to 6 sec. and many signal controller units will not permit settings outside of this range. If the phase change interval needs to be near the top of this range or beyond, the additional time is sometimes provided as part of a red clearance
interval.

It's also legal in Canada, or at least Ontario. The OP is a moron. You may always enter the intersection to perform a manoeuvre you have a green light for (in fact, the HTA says you can receive a ticket for NOT doing so). Once you are fully in the intersection, if you light turns red because you cannot complete the manoeuvre you are permitted (and required), by the HTA to complete the manoeuvre on red.

Yes, you must wait until the intersection is clear, that is also in the HTA, however, that is much more discretionary than the other directions, since the driver may start their left turn and realize the intersection is not clear before they complete their turn due to a blocked view or a car speeding up, at which point the driver is required to yield the right of way.

Furthermore, while it is horribly annoying when people overstep this and try to squeeze three cars though, it present absolutely no collision risk because the left turn is complete either during the time when the whole intersection is red (yes, the entire intersection is supposed to be red for a moment before the other traffic is allowed to move) or as the other light turns green (in which case they are stopped and notice you in their path so they wait to proceed). The only possible time I can see it being a problem is when a driver decides to speed at a stale red, not paying attention to the intersection, in the hope that the intersection will be clear and the light will magically turn green. That sort of driver was planning to run the red, anyways.

I *have* driven in an area where left turns on red are "illegal" (Philadelphia) and they aren't really illegal as far as I can tell. Instead, the left turn lights turn RED after they give you an opportunity to do a protected left turn. Notice that in the first paragraph I mention the driver must have a green light when they enter...

Cities ABSOLUTELY cheat on yellow light timing - and they always will be because after they sign the contracts, they realize just how much money they HAVE to bring in just to pay the minimum monthly fees to the camera companies.

Case in point: In Paradise Valley, Arizona, they were caught red-handed by anti-camera activists intentionally shortening yellow lights [wordpress.com] going less than four seconds, which was a threshold they were never supposed to go under. The city claimed they weren't doing it, until this youtube video [youtube.com] proved they were cheating at photo radar intersections.

After being caught red-handed, the city quietly and quickly - the very next day, in fact - changed the timing to match that minimum threshold.

In downtown Chandler, AZ, there was another well-known intersection with cameras with a shorter yellow time than the others, and it led to a majority of ALL of its camera "revenue".

Bottom line: There are a ton of revenue-desperate city councils out there full of dopes who aren't clever enough to see what the snake oil salesmen from camera companies are selling: "sin tax safety" AND revenue to boot, with a huge gotchas attached. It's going to take years to flush the system of these safety-neutral, revenue positive cameras.

BTW - Everyone should take notice that Los Angeles hasn't burned to the ground after turning off their cameras. It's safe to say that if LA can live without cameras, Denver (and any other major city in the United States) would probably avoid their own "carmageddon" as well...

I've driven in a dozen states, all on the east coast of the US. In those states, this is not only permitted, it is the correct thing to do. It is taught that way in driver's education and a traffic cop will direct you to do this as well. When the light turns red, the driver in the intersection completes the left turn. It is not dangerous because there are a few seconds where the light remains red specifically as a time to clear the intersection. The only problem I've ever seen is when bad drivers either stay in the intersection and block it, or back-up - both of which are illegal.

For the Google-challenged:
http://www.thenewspaper.com/news/02/243.asp [thenewspaper.com]
http://www.thenewspaper.com/news/28/2887.asp [thenewspaper.com]

You can find more.

However, I changed my mind once a I listened to a local police chief explain that in his city traffic accidents had actually risen at the intersections where the cameras were in use.

This is not unusual. The Federal Highway Administration found that red-light cameras increase rear-end collisions but reduce more severe right-angle collisions, saving $50,000 in collisions per intersection per year in medical and repair costs. [tfhrc.gov]

If you are in the intersection when the light turns red, you have the right of way to clear the intersection before anyone else goes. It's really pretty simple and no cop or red light camera anywhere in the US should give you a ticket for it.

Do you even understand the theory behind yellow lights? You said it doesn't matter how long the yellow is so thus a .00001 second yellow is ok? Based on your assumptions we don't even need a yellow light at all because you should just stop when you see red, right?

If you are moving at 45/50 mph and the light turns yellow for a second then you may not even have time to stop at all let alone safely if you are already near the intersection. You seem to be assuming you can stop a car instantly and safely the second you see the yellow light. This is not always the case. A longer yellow allows cars that can't safely stop to continue though the intersection during the grace period and warns cars that have enough time to stop to do so. The problem is, unless the speed limit is extremely low, shorter yellows force drivers to make the "stop" decision more often and in more dangerous situations. It is also important to remember people have reaction times that are not instant.

I know these cases are not everyday for an individual person but at almost every light change someone is being forced to make the decision of stopping or continuing shortening the yellow.

I don't think we want to live in a world where the second a yellow is up we must smash our foot to the ground and use ABS just to be sure the light doesn't turn red before we cross into the intersection.

That is the point of a yellow as opposed to just having green and red. it is legal to enter the intersection on yellow, whether it's a fresh or stale yellow. It is illegal to enter on red. The reason is when the light changes you may only be 5' from the intersection, or 20', or some other distance where stopping is either not possible or not safe. A sufficiently long yellow (IIRC 1 second for every 10 MPH of traffic speed) virtually eliminates red light runners, a brief overlap of red prevents the occasional oblivious driver entering on a fresh red from causing an accident.

I will say around here since they started putting up red light cameras I now slam on my brakes if there's any hope I may be able to stop. Had a few close calls almost sliding into the intersection and also damn near got rear ended a couple times. Not my problem though because the State is obviously more interested in revenue collection (hidden taxes) than safety. A red light camera (and of course the State) doesn't care if the road is wet or icy, or any other scenario that would make it safer or more prudent to proceed through a yellow even if it's a stale yellow. I won't take the chance of getting fined for doing something safe, I'd rather get rear ended and take that to court for a new paint job or new vehicle. You can win against someone else who caused an accident by inattentiveness or following too closely, you can't win against the State as the deck is stacked heavily against you.

Also red light cameras have caused me to make the occasional illegal uturn, or reverse down a road rather than proceed on red. This is when the light will never change or will go through several cycles and never turn my side green. Typically this happens more often later at night when tehre is less traffic on the road. Normally after waiting at a light for 5-10+ minutes with no traffic on the road I'd assume it won't change and treat it like a stop sign so long as I have good visibility both directions. Instead with red light cameras I'll make an illegal uturn or illegal reverse and take an alternate route, so as not to get a fine.