A man who displayed a “Cops Ahead” sign to warn drivers of a police trap on a suburban street and was arrested now has been given permission to sue the officers.

According to a description of the case by Courthouse News, a ruling from the 2nd U.S. Circuit Court of Appeals lets Michael Friend pursue the city of Stamford for First Amendment violations and malicious prosecution.

“Friend was violating no law by standing on the sidewalk and displaying his sign, and [Police Sgt. Richard] Gasparino had no lawful reason to order him to desist from that conduct,” the appeals court ruled.

The appeals court said the sign was protected speech because it expressed an opinion on “a matter of public significance” and, “[A] citizen does not need to show that a police practice is unlawful – or that it deviates from some notion of propriety – in order to object to it.”

A trial court judge had sided, previously, with Gasparino, the arresting officer.

The report said Friend’s protest happened April 12, 2018, “as he stood on a sidewalk with his handmade poster two blocks from a police trap to catch drivers using their cellphones. After Sgt. Gasparino told him to leave the scene and took the sign, Friend moved one block farther from the operation, to a gas station where a supportive worker provided a bigger piece of cardboard to fashion another poster.”

Gasparino then arrested Friend for “police interference.”

He was held behind bars until 2 a.m. when he was released on his own recognizance. Gasparino had demanded a $25,000 bail.

The charge against Friend was dropped shortly later, after the prosecutor admitted Friend actually had helped police “do a better job than they anticipated because, when [drivers] saw the signs, they got off their cellphones.”

Friend’s three pending claims cite the First and Fourth Amendments.