JOPLIN, Mo. — Flashing headlights can actually mean a few different things, depending on the context.

Fortunately, it only takes a second to check the two most common things the other driver is trying to communicate: Your own headlights, and the potential dangers ahead of you on the road (and despite what you may have heard, it’s not a gang initiation ritual.)

(Image courtesy: Getty Images)

But a quick flash of the headlights typically means the presence of law enforcement ahead, with radar, trying to catch speeders.

So the question becomes, is it legal to flash your headlights for this reason?

In some states it used to be illegal to flash your headlights to warn other drivers about a speed trap. The American Civil Liberties Union (ACLU), has stepped in numerous times across the country representing individuals concerning this subject.

Basically, every state has different rules regarding flashing lights as a warning. However, with the Supreme Court ruling in Spence v. Washington, it’s safe to say outdated municipal ordinances about this issue don’t hold water.