You see it all the time. Oncoming traffic has one individual that seems to want everyone on the road to know that they're there as they won't dim their high beam headlights. So is it illegal to flash your headlights at this oncoming vehicle? No, not if it's for that reason, but what if you're driving down the highway and you see law enforcement set up with radar trying to catch speeders?

In some states it used to be illegal to flash your headlights to warn oncoming vehicles about a speed trap but for drivers in Missouri that changed a number of years ago.

Back in 2014 in federal court in St. Louis, a judge ruled that drivers are allowed to flash their lights to warn other motorists of nearby police and speed traps. The order by U.S. District Judge Henry E. Autrey in St. Louis, ruled that it's a first amendment right for drivers to do so.

Of course sometimes the flashing of headlights are also done to warn motorists of a wreck or a different situation ahead, i.e., to slow down.

The ACLU (American Civil Liberties Union) has stepped in numerous times across the country representing individuals concerning this subject. The particular ruling for Missouri was from a driver that was cited for flashing her headlights in 2012 in Ellsville, MO. Michael Ellis had flashed his headlights to notify motorists of radar set up in Ellsville.

According to a story in 2014 from Foxnews.com:

Ellisville City Attorney George Restovich said the city changed the policy after the case went to court and no longer pulls over people for flashing headlights.

 

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