Can you give a New Jersey cop the middle finger? Here's what to know.

William Martin raised his middle finger at a New Jersey police detective, and he got slapped with a ticket.

He was charged with disorderly conduct in New Milford, Bergen County, in 2016.

The ticket he received said this: “Behaved or exhibited disorderly conduct, specifically by extending his left arm out the driver’s side window and raise his left middle finger [at the officer].”

But the case was dropped by the county prosecutor because flipping the bird is a First Amendment issue.

It turns out, the "New Jersey salute" is considered free speech.

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“When I received a summons, I felt that my free speech rights were under attack for nothing more than expressing my frustration with someone whose driving had put people at risk,” Martin said, according to the ACLU of New Jersey, which represented him in court. “I’m relieved to know that the town of New Milford recognized it wasn’t worth prosecuting me for expressing my frustration.”

Legal precedent has firmly established that a raised middle finger, even one directed toward a police officer, is an act of speech protected under the First Amendment, according to the ACLU.

“Enforcing manners rather than public safety is a poor use of police resources,” said ACLU-NJ Deputy Legal Director Jeanne LoCicero, who represented Martin. “It might be rude to flip off a police officer, but it isn’t a crime.”

Most arrests for use of the middle finger are put in the disorderly conduct bucket. New Jersey law has two pieces to its disorderly conduct statute: improper behavior and offensive language. The behavior involves fighting or threatening behavior or creating physically dangerous conditions.

So, the middle finger is protected speech, but threatening a police officer in any form is not.

This article originally appeared on Asbury Park Press: Can you give a New Jersey police officer the middle finger?