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Denver Must Prove Red-Light Cameras Improve Safety

Posted by timothy on from the welcome-to-the-red-light-district dept.

An anonymous reader writes "An audit of accidents at Denver intersections where red light cameras were installed versus increasing the length of the yellow light shows little difference in the results. In a case of putting the public ahead of the corporation, the Denver auditor is recommending canceling the red light camera program unless the city can prove a public-safety benefit." I hope that private citizens offering analysis or recommendations are treated fairly.

7 of 433 comments (clear)

  1. I Seem To Recall by sycodon · · Score: 5, Informative

    ...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.

    --
    When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
    1. Re:I Seem To Recall by digitalaudiorock · · Score: 5, Informative

      As I recall, cities were in fact called out for shortening yellow lights for profit, and risking lives in the process. A quick Google search found this: http://blog.motorists.org/6-cities-that-were-caught-shortening-yellow-light-times-for-profit/

    2. Re:I Seem To Recall by bjdevil66 · · Score: 5, Informative

      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 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 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...

  2. Re:Are yellows in Denver really short? by Anonymous Coward · · Score: 5, Informative

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

  3. Re:Are yellows in Denver really short? by Attila+Dimedici · · Score: 5, Informative

    I have seen several studies showing a very distinct link between length of the yellow and safety. This study shows that increasing the length of the yellow decreases red light violations and this article references several studies that show that this effect does not diminsh with time. So, your gut is wrong on this one (although I understand why you would suspect that to be the case).

    --
    The truth is that all men having power ought to be mistrusted. James Madison
  4. Re:Are yellows in Denver really short? by Anonymous Coward · · Score: 5, Informative

    "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

  5. Re:The MUTCD and ITE by Anonymous Coward · · Score: 5, Informative

    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.