A police official in Arizona has been placed on administrative leave after showing up armed to a student-led protest and provoking an altercation that led to the arrest of a teenage girl. The officer told fellow police who arrived on the scene that he attended the students’ immigration rights protest with the intent of acting as an agent provocateur, according to a news report.

Dusten Mullen, a sergeant with the Phoenix Police Department, has been suspended with pay pending an internal review of his conduct at a protest at Hamilton High School in Chandler, Arizona, on January 30, according to Phoenix Police Chief Matthew Giordano.

“As law enforcement professionals, we are held to higher standards of conduct — both in and out of uniform,” Giordano said. “When we fall short, we must be accountable, and we will not tolerate actions which undermine the trust the community has placed in the Department.”

Fox 10 Phoenix, the outlet to first identify Mullen, reported that Mullen told Chandler Police Department officers on the scene that he was there in the hopes of getting a rise out of the kids that would then allow the local cops to cuff them.

“My plan is legitimately to just let them all assault me and you guys arrest them all and I’ll keep it on film,” Mullen said, according to a police report obtained by the local TV news site. “I also have other people filming from a distance.”

The protest at Hamilton High School was one of dozens of student-led walkouts that took place across the greater Phoenix area that day, coming just over a week after the killing of Alex Pretti by Customs and Border Protection officers in Minneapolis. At Hamilton High, several hundred students walked out and rallied along a thoroughfare, chanting and holding signs decrying U.S. Immigration and Customs Enforcement.

Mullen, who in 2025 drew a salary of $336,518, is suspended with pay and was required to surrender his badge and gun pending the outcome of the investigation, according to a spokesperson for the department.

Steve Serbalik, an attorney representing Mullen, said his client was within his rights as a member of the public to voice his disagreement with the students.

“Placing Sgt. Mullen on administrative leave and issuing a media advisory that suggests misconduct based solely on his lawful, off-duty expressive activity appears to chill the exercise of constitutionally protected speech and risks violating both federal and state constitutional guarantees,” Serbalik wrote in a letter sent Monday to Giordano and shared with The Intercept. “I respectfully urge you to immediately reconsider and lift the administrative leave, withdraw or correct the media advisory, and ensure that any ongoing review fully respects Sgt. Mullen’s constitutional rights.”

Gun at Teenagers’ Protest

Mullen’s appearance at the protest sent a wave of fear through some attendees. Megan Craghead, whose 18-year-old son attends Hamilton High School, showed up that day because her 13-year-old daughter wanted to take part in the protest. Craghead told The Intercept it was a peaceful, upbeat scene, and most passersby honked in support of the rally.

That changed suddenly when a pair of girls came running toward her yelling about a man with a gun.

“He was just walking up and down the sidewalk, talking kind of smugly and yelling at the kids,” Craghead recalled. “It felt like something that could easily escalate into something that’s going to be traumatic for all of these teenagers.”

As soon as she heard about an armed man on the scene, Craghead sent her daughter away with Craghead’s sister.

“We had no idea why he was there, he’s wearing a mask, and even if he did not plan to use his gun, we still don’t know what’s going to happen, right?” Craghead said. “We had all just witnessed the shooting of Alex Pretti, where he was at a protest with a gun and he ended up getting shot and killed. And so even if this armed person did not touch his gun, we still don’t know what’s going to happen.”

In a TikTok video from the scene, Mullen was seen in a T-shirt emblazoned with an American flag and the words “Trump 2024” and “We took the country back.” He concealed his face with a neck gaiter and wore a handgun, along with several extra magazines on his hip.

Surrounded by young people jeering at him, he told a Chandler Police Department that he had been assaulted as he appeared to record the scene on a cellphone.

“Nobody assaulted you,” one person told Mullen.

“Grown-ass man, out here with a gun crying about a little kid,” another person said.

In the wake of the incident, the Chandler Police Department told reporters that a girl was arrested for throwing a water bottle at Mullen, but video of the incident published by Fox 10 appears to show just water — no bottle — hitting him. The charges against the girl were later dropped by the Maricopa County Attorney’s Office.

A spokesperson for the Chandler Police Department did not respond to multiple requests for comment.

Department With a History

Chandler, a city of about 275,000 people, lies in an area known as the East Valley, and its deep-purple electorate is not particularly known for progressive activism. Amid the deadly immigration crackdown in Minneapolis and heightened border tensions in Arizona, however, many students could see a direct impact on their own lives or those of their friends, according to Craghead.

“They’re seeing a lot of their friends that are immigrants or have immigrant families feeling really scared right now,” she said. “There’s a lot of things happening in politics that are not directly affecting the lives of teenagers, but this is one of those things that they can see has a direct impact on their own lives.”

Bill Moore, a defense attorney in Phoenix, said he was pleased to see Mullen placed on administrative leave, citing the department’s history of frequently failing to hold its personnel accountable — part of a pattern of misconduct and impunity severe enough to trigger a civil-rights probe by the Justice Department in 2024.

“The ‘blue line’ thing is still very much a thing here,” Moore said, referring to an unwritten code where police look out for one another instead of pursuing complaints about misconduct. “That they took this action tells me that their internal investigation must be fairly damning.”

The revelation that the armed man who showed up to the protest in January was actually a cop sent ripples of anger through the community, according to Brandy Reese, a co-leader of the local Indivisible chapter for Chandler and the neighboring city of Gilbert.

“I find it especially upsetting that he went there armed,” said Reese, who was observing the protest that day from the sidelines. “Why did he feel he needed to do that? I think the whole situation is unfortunate and upsetting.”

Craghead, the mother of the protest attendees, said her opinion of what should happen to Mullen has gone back and forth in the days since she learned that a police sergeant was the masked, armed man who she had seen trying to pick a fight with the kids at the rally. After an initial reaction of wanting his immediate termination, she wondered if he wasn’t within his First and Second Amendment rights to show up, off-duty and armed.

The more she’s thought about it, she said, the more she’s felt anger at his conduct.

“We have a duty to hold our public safety officers to a higher standard. If this was a regular person that had come to counter-protest and they happened to bring their gun, that would be one thing,” she said. “The issue is that he went there with the purpose of agitating children to get them to break the law so that they could be arrested, or worse. So now I’m back to thinking he should be fired.”