The only person to go to trial after blocking a St. Paul freeway during a protest of the police shooting of Philando Castile saw his conviction overturned on appeal Monday.

Jeffrey Berger argued before the state Court of Appeals that the guilty verdict of misdemeanor public nuisance was unconstitutional, and the three-judge panel ruled in his favor and possibly sent a signal to law enforcement about what forms of protest warrant arrest and prosecution.

The court agreed with 77-year-old Berger’s contention that “the state did not present sufficient evidence to establish,” as state law requires, “that he personally interfered with, obstructed or rendered [Interstate 94] danger for passage” on that night in July 2016, soon after Castile was shot by then-St. Anthony police officer Jeronimo Yanez during a traffic stop in Falcon Heights.

The City Attorney’s Office in its prosecution “failed to prove beyond a reasonable doubt that Berger entered I-94 before” passage on the highway was obstructed or made dangerous.

Berger, of Minneapolis, was one of 44 people prosecuted by the city of St. Paul for protesting on I-94, according to City Attorney Lyndsey Olson.

Of those, she said, 43 pleaded guilty, and Berger’s was the only case that went to trial. Felony riot charges against one other protester were eventually dropped.

Last year then-Gov. Mark Dayton vetoed a GOP-backed bill that would increase penalties for protesters who block freeways or transit lines.

There’s no disputing that Berger was on the interstate with others, some linking arms and chanting over the course of the 5-hour demonstration.

Berger went so far as to tell police that he was unwilling to leave and ready to be arrested. And so he was. He was acquitted on an unlawful assembly count but found guilty of creating a public nuisance. He appealed his conviction with the backing of the American Civil Liberties Union of Minnesota.

Berger’s attorney, Pari McGarraugh, said in an interview that her client benefits personally by not having on his record a “conviction that wasn’t fair and didn’t reflect the evidence against him.

He also doesn’t have that “stigmatic injury” that comes with being found guilty, McGarraugh added.

In broader terms, McGarraugh said, this unanimous ruling “means that an individual person can participate in [legal] protest action without being held responsible for the actions of others.”

She said the problem is that the public nuisance statute is written too broadly and allows any law-abiding protester to be scooped up and arrested amid others who clearly are lawbreakers.

“The concern is the statute, read by its extremes, means that you could be arrested simply for standing on a sidewalk — on theory that the sidewalk is a public right of way — and interfering with people’s free passage.”

Had Berger lost his appeal, she said, “we absolutely were prepared to appeal. The constitutional issues at stake here are extremely important, and this statute is still vulnerable” to repeated challenges in court if not written off the books in the Legislature.

Berger’s victory does not change how the statute in its current form is applied going forward, she said.

“I don’t have a ton of lobbying experience,” McGarraugh said, “but maybe it would be prudent for the Legislature to address it.”

In response to the Appeals Court ruling, Olson said, “Reversal of the jury’s determination in this instance is an example of the legal nuances in holding individuals accountable for collective action.”

Olson said Monday night that she is not interested challenging the reversal in the state Supreme Court.

McGarraugh said that Minnesotans are a particularly socially conscious bunch, whether about war, guns, abortion or police conduct.

“The group march is a time-honored tradition and constitutionally enshrined,” she said. “This is a huge deal for the issues that are stake and the civil liberties that are at stake for the future of our democracy.”