Why Louisiana State Police Flash Lights Facing Oncoming Traffic: A Safety Move Explained

LAFAYETTE, La. (KPEL News) - Have you ever noticed Louisiana State Police vehicles parked along highways with their lights flashing, facing oncoming traffic? While it may seem like a tactic to catch speeders, it’s actually part of a safety strategy designed to prevent accidents.

According to the Louisiana State Police, this practice is known as “traffic queue warning.” Officers use it to alert drivers to slow down ahead of congested or stopped traffic, reducing the risk of rear-end collisions. This method becomes especially critical in construction zones or after accidents, where sudden slowdowns could otherwise catch drivers off guard.

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A Facebook post from the State Police highlighted this practice in action on I-20 in Ouachita Parish, where officers used their vehicles to provide advanced warnings for nearby construction crews. By slowing traffic early, workers remain safer, and drivers avoid sudden braking that can lead to accidents.

"On I-20 in Ouachita Parish, Troopers are providing advanced warning for construction crews working to improve our roadways," the Facebook page explained. "Please reduce your speed and use caution in all construction zones so these men and women can safely return to their families."

Stopping distances also play a role—at 70 mph, cars need over 380 feet to stop, while loaded trucks require more than 550 feet, according to the National Association of City Transport Officials. That's nearly one-and-a-half times the length of an American football field. It's a significant distance needed for braking.

On high-traffic routes like I-10 or I-49 near Lafayette, early warnings are crucial in preventing pile-ups.

Next time you see those flashing lights, slow down and stay alert—it’s one of many ways law enforcement works to keep Louisiana’s roads safer for everyone.