A federal judge has ruled that under the First Amendment, drivers are allowed to flash their headlights to warn others of police speed traps. The case stems from the arrest of a Missouri man.

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U.S. District Judge Henry Autrey ruled that not only is the act protected speech, but said that police are not allowed to enforce the state law prohibiting it.

On Fox and Friends, Judge Andrew Napolitano said that in his home state of New Jersey, there is no law against this, but cops still ticket people for interfering with free flow of traffic.

“Are the police more interested in collecting revenue from tickets, or having people drive safely?” Judge Napolitano asked.

He said it’s likely other federal courts will follow with similar rulings.

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