Late on a Saturday night three months ago, Austin police tackled a man on Sixth Street as dozens of revelers swarmed around to watch the drama.

Well-known police accountability activist Antonio Buehler, whose group Peaceful Streets frequently deploys across the city to film officers on patrol, raced — with cameras rolling — to film the action.

Officers, including Corey Jewell, began yelling at Buehler: “Back up! Back up right now!” and placed themselves in front of the camera. “You aren’t going to be that close to us!” Jewell shouted.

Minutes later, shift supervisor Sgt. Thomas Hugonnett was confronted by Buehler, who says Jewell deliberately stuck his crotch in his face while he was kneeling down to shoot video.

“I know you’re a pig (expletive) who can’t control your people,” Buehler shouted. “I know you’re a pig (expletive) who doesn’t respect civil rights.”

Videos of the incident — one taken by Buehler and the other by a small body camera Hugonnett was wearing — help illustrate what police officials and others describe as escalating tension between officers and camera-clicking citizens, leading to arrests of photographers and allegations of misconduct against police.

In a digital age when videos can easily be uploaded to the Internet, an array of footage by both police and citizen-photographers reviewed by the American-Statesman shows how the national trend of cop-watching is playing out on Austin’s streets.

In the several years since its cameras started rolling, Buehler’s group has documented thousands of hours of Austin police activity and produced videos highlighting police misconduct and creating internet sensations. The work has generated millions of clicks on YouTube.

But as this video of the Hugonnett-Buehler exchange shows, the Peaceful Streets activists aren’t always just observing. Name-calling and what police describe as taunting are also common, and police say the activists brush up against the boundaries of the law by interfering with their work and putting them in danger.

On the other hand, filmers say Austin police have delivered their own brand of harassment, at times forcing them to stand back farther than other members of the public who don’t have cameras, pushing the limits of what constitutes “interfering” with their jobs and blocking them from getting footage of unfolding scenes, as this video shows.

Some fear the friction could spin out of control.

“It’s not going to take much of a spark to cause a fire,” said Austin police Lt. Todd Smith, who works downtown and has routinely witnessed interactions between activists and officers. “It has the potential to become a dangerous situation. I’m afraid it is going to embolden somebody to do something that causes an unmanageable situation for the police officers.”

In an interview with the Statesman, Buehler said he has no intention of creating a danger. He said he gets angry only when police officers are violating his right to record them.

“How are we antagonistic by filming?” he said. “We are only antagonistic by filming the police if the police have something to hide. We have every legal right to be down there filming.”

Austin Police Monitor Margo Frasier said she has recommended to Buehler and his group and to Police Chief Art Acevedo that they attempt to develop an understanding — possibly by meeting with a mediator — about how police watchers and officers interact and comport themselves, particularly downtown.

“That conversation always becomes more difficult when you haven’t had it in the first place, and when you let things fester, the conversation always becomes harder to have,” she said. “But I still think that’s what needs to occur.”

Civilians filming police goes back decades, with the 1991 beating of Rodney King in Los Angeles being one of the first instances in which citizen video shook public consciousness. Four police officers went to trial on state criminal charges, but the cases didn’t result in convictions and were blamed for triggering riots.

In more recent years, however, such police scrutiny has become common nationally with the proliferation of cellphones that make it as easy as pointing the camera and tapping “record.”

Nationally, experts say filmers are often divided into two broad categories: those who simply reach for their phones when they witness a dramatic police interaction and others, like members of Peaceful Streets, who operate in a coordinated effort, use more high-tech GoPro cameras and seek to more broadly document police activity.

“There are crusaders out there who are definitely trying to cause sensationalism, and I think there are others who are really legitimate who are trying to document what happened,” said John DeCarlo, an associate professor of criminal justice at the University of New Haven in Connecticut.

No matter the motive, the experts say the increasingly common practice of recording officers has helped provide crucial evidence in cases in which officers erred — or possibly erred — especially when they might have otherwise escaped discipline or criminal charges.

One of the best-known recent cases happened in April 2015 in South Carolina, where an officer fatally shot an unarmed fleeing man. A witness filmed the shooting, and what is seen in the video challenged the officer’s account of what happened.

The man who recorded the shooting at first didn’t release the video because, he said, he feared retaliation. Once he did, the video was aired repeatedly on national media, and authorities arrested the officer on a murder charge. He also faces federal charges of civil rights violations.

Yet some experts and police advocates fear such videos are unfairly skewing public perception of police — that videos tell only part of a narrative without regard to a suspect’s behavior before the cameras started recording.

DeCarlo said video of use-of-force encounters can particularly astound viewers who aren’t accustomed to seeing what he said is often required of officers.

“We are not used to seeing it in our daily lives, so when we look at this, it is always shocking when an officer uses a weapon or pepper spray or Tases somebody,” he said. “Even when it is within the Constitution or local policy, it is unpleasant to watch, and we have a negative reaction, even if the force was justified.”

Peter Moskos, a John Jay College of Criminal Justice professor, said even though publicly taken video is helpful, it isn’t foolproof.

“The problem with video is that when someone starts filming, you missed what led to the action in the first place, so you aren’t getting the whole story,” he said.

At times, the practice of capturing video of the police — and the technology giving rise to the trend — has outpaced federal and state laws and local policies.

Federal court rulings make clear that recording police activity is generally legal.

The U.S. Supreme Court hasn’t specifically considered the legality of filming the police, but a ruling earlier this year by a federal judge in Pennsylvania made the issue more murky. He ruled that citizens aren’t constitutionally protected when they film police, unless they are doing so with the purpose of criticizing police activity — not just out of interest or entertainment. But the ruling sets no legal precedent, experts have said.

In Texas, no law specifically addresses filming of police. Last year, a Dallas lawmaker proposed legislation that would have required a private citizen to stand at least 25 feet away when videotaping officers. The measure quickly died.

However, the law says no one, including photographers, is allowed to interfere with the duties of a public servant, a Class B misdemeanor for which filmers face arrest.

Rob Kepple, director of the Texas District and County Attorneys Association, said that the law is broad and that a successful prosecution “obviously has to be more than filming. It’s filming plus something else that makes it difficult for the officers to do their jobs.”

In Austin, Peaceful Streets isn’t the only group filming the police, but it is the most well-known and controversial.

Other groups have worked more collaboratively and calmly, officials say. That was the case, for instance, in March when a photographer for the accountability news site Photography is Not a Crime was filming police. The photographer, Phillip Turner, used his footage to direct police toward a man he saw grip what appeared to be a handgun during a fight downtown on the final night of the South by Southwest Music Festival.

“Police officers — not all, but generally — do not like being recorded,” Turner told the Statesman at the time. “In this case, my film helped them get a guy off the streets.”

But the most notable group is Peaceful Streets, which emerged in 2012 after an encounter between Buehler and Austin police officers.

According to the organization’s website, Buehler witnessed a drunken driving investigation near downtown, objected to the treatment of a passenger and started recording. Minutes later, he and officers had a heated exchange about his actions, Buehler said, resulting in his arrest on a felony charge. Buehler was acquitted.

Over the past several years, the organization has posted videos that went viral.

“The primary reason we cop-watch is to deter police abuse, crime and violence while we are on the scene,” Buehler said. “The only escalation comes from police.

“Some people are upset that we curse at the police,” he said. “That is constitutionally protected and legal to curse at the police in response to the police committing crimes right in front of us.”

In the past few years, the clashes have resulted in more than shouting matches. They also have led to the arrest of photographers as well as allegations and discipline against police officers.

According to Austin police policy, officers aren’t allowed to tell a citizen that filming isn’t allowed “as long as the photographing or recording takes place in a setting … at which the individual has a legal right to be present” and the citizen “does not interfere with the officer’s safety or lawful duties.” Officers also are prohibited from “intentionally blocking or obstructing” cameras or threatening or intimidating photographers.

However, police say it often is necessarily to establish a perimeter with officers to create working space and to prevent a scuffle from spreading. Filmers say that line of officers is also used to block their view.

A review of documents from the Austin police monitor’s office shows that videos were used in three complaints by the public in 2013 and 2014 but that the number went up to 11 in 2015. Those complaints have resulted in eight disciplinary actions against officers since 2013.

One of the most severe punishments was three years ago against Detective Ricky Jones. A disciplinary memo said he refused to identify himself and made statements that could be perceived as threats toward a citizen. “Detective Jones admitted that the citizen had a legal right to stand on public property and film him,” the memo stated.

Police have arrested several filmers, but none of those cases has resulted in a conviction.

Most recently, officers arrested Peaceful Streets member Kenneth Holmes on a charge of interference after, they said, he refused to stand back as officers responded to two separate fights. An arrest affidavit said he was in the space police needed to control the fight and keep officers safe.

Assistant County Attorney Dan Hamre said that when prosecutors review cases in which a suspect was arrested and accused of interfering with officers, they consider whether the defendant got involved physically in a confrontation and the number of times the person was warned to stop.

“It’s legal to do, up until a certain point,” he said. “The question is where is that point? We have to look at the facts of each case. The bar is high in most of these cases.”