I always thought this was the case

A Florida man was driving home one day and he saw a Seminole County Sheriff's car parked of the road in a speed trap.  So the man started to flash his lights to oncoming traffic.  Only one of those cars was another deputy, who promptly gave him a ticket.  Well, our hero fought the police action on two grounds.  First he said that the statue they county relied on was not intended for flashing your headlights but rather to prevent average citizens from using flashing emergency lights on their cars while driving down public ways.  Second, he said he was using his headlights to communicate with the on-coming drivers.  Therefore, any attempt to stop him was violative of his First Amendment right to free speech.  Both arguments had great merit.  He could have one on the first grounds that the sheriffs overreached to apply the emergency light statute.  However, the judge took on the Constitutional issues.  And the driver won.  So people, feel free to freely express yourself.  The next ticket that is saved may be your own.