Flashing your high beams to warn other drivers about a police officer ahead, possibly with radar out looking for speeders, is one thing most of us do and appreciate when someone warns us.

Now, I will tell you that if someone is going exceptionally fast in an area that is truly unsafe for speeding, I don’t flash at all.

Anyway, even if a cop isn’t ahead, those flashing lights also communicate to slow down, stay alert, and be cautious because something is going on up ahead.

Regardless of the reason, it’s a great way to capture someone’s attention. You’re warning them that something’s up and that something could be a speed trap ahead.

So, is it illegal for you to flash your lights and warn the oncoming driver?

Is it technically obstruction of justice?

For decades, this was illegal, but according to KTLA, this all changed in 2014.

A federal court in St. Louis, Missouri, ruled that it’s your First Amendment Right as a licensed driver in the United States to flash your lights if you want to warn other motorists about a speed trap.

The police cannot retaliate against drivers who have done nothing wrong and are simply exercising their right to communicate with other drivers.

Even the American Civil Liberties Union (ACLU) has stepped in around the country to represent people.

READ ON: Why Police Ask These 4 Questions After Pulling You Over

This national ruling came from a Missouri case where a driver received a citation after he was caught flashing his lights to notify motorists about a speed trap.

There is also the little-known 1974 United States Supreme Court ruling in Spence v. Washington, which addresses non-verbal free speech as well.

Even if this law is still on the books somewhere in the country as obstruction of justice, it shouldn’t hold if you decide to fight it.