Did an Improperly Timed Traffic Signal Cause Your Client’s Accident?

Your client has been in a traffic accident and turned to you for help…and you suspect that the traffic signals caused the accident. Properly timed traffic signals regulate traffic flow, allowing drivers enough time to cross intersections or stop safely. However, many accidents occur at intersections and other places controlled by traffic signals. 

A traffic signal can be a contributory cause of an accident due to improper timing, especially the timing of the yellow light. And if you suspect that improper yellow light timing contributed to or caused the accident…then we may be able to determine if the city, county or state is wholly or partially responsible for the accident, which may possibly allow you to win greater compensation for your client.

Can a Traffic Signal Cause Your Accident?

Statistics show that properly timed yellow lights reduce the incidence of traffic collisions, particularly those involving running red lights. So, what can make a traffic signal cause your accident? Take the example where the yellow light is set too short. In this case, the timing can increase the risk of collisions, as your client may have been forced to make a sudden stop or to run the red light to prevent possible rear-end collisions, only to end up in an accident with cross traffic.

This scenario is an excellent example of how the timing of the yellow light may contribute to the accident, and why it’s crucial for driver safety that traffic managers modify signal timing regularly to reflect current conditions.

Local Control of Yellow Light Timing

Standards dictate that a yellow light should last approximately 1 second per 10 miles per hour of the posted speed limit (Please see the accompanying chart from the California 2014 MUTCD). Traffic managers set the actual timing of yellow lights according to local traffic patterns and conditions. For example, if accidents often occur at a particular intersection, traffic engineers can adjust the yellow light timing to give drivers more time to stop safely. 

Yellow Light Timing Chart. Please visit https://dot.ca.gov/programs/safety-programs/camutcd for the most up to date MUTCD.

The local DOT might also increase the time between a light turning red and the cross-traffic light turning green, allowing the intersection more time to clear before permitting cross-traffic to proceed. In other situations, vehicle sensors installed at intersections can dynamically change traffic signal timing based on traffic volume, time of day, or weather. 

Regardless of local DOT practices, Chapter 7 of the Traffic Signal Manual from the Federal Highway Administration states that “It is generally considered good engineering practice to retime traffic signals every three to five years.” This practice allows traffic managers to adjust timing to reflect new traffic volumes, patterns, and conditions. If they haven’t changed the signals regularly, we may be able to investigate the traffic signal’s maintenance records and other information to potentially help your case. 

Turn to Glucroft Investigations for Help

If you have a client involved in a traffic accident and you suspect the traffic signal caused their accident, Glucroft Investigations can help you determine if improper signal timing is a contributing factor. We are experts in acquiring information related to traffic signals, their timing, and maintenance history that may prove the traffic signal contributed to the accident and put the city, county or state at fault.

Call us at 866-411-8646 or use our Contact Form and let one of our experienced investigators go to work on your behalf.


This article is not meant to offer legal or insurance advice. Please contact your appropriate legal or insurance professional for advice concerning your particular situation.

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