Fired Phoenix sergeant accused of using rank to 'intimidate' Chandler officers months before controversy

Chandler councilman reacts to Dusten Mullen's conduct

Councilman OD Harris criticizes former sergeant Dusten Mullen following reports of him using his rank to intimidate officers at a crash scene.

PHOENIX - On April 30, 2025, Chandler police responded to the scene of a traffic collision at the intersection of Arizona Avenue and the Loop 202 Santan Freeway just after 9 p.m. A T-bone collision involved two cars, and one of the drivers is the son of then-Phoenix police sergeant Dusten Mullen. When Mullen arrived at the scene, Chandler police say he identified himself as a Phoenix officer.

The backstory:

An internal email from Chandler Police Sergeant Brian Lutt, sent to colleagues the day after the accident, outlines the encounter. The subject line states: "Off duty Phx Sgt. behavior on the scene of an accident. He made it a point of identifying his rank and agency, then conducting himself in an unprofessional, confrontational, accusatory manner which delayed the investigation."

The email says when Mullen was asked if an officer could take a photo of the digital insurance card on his phone, he refused, saying he "knows the law" since he’s a sergeant with the Phoenix Police Department. According to the officer, Mullen said he didn’t trust Chandler police because two officers had "slept with his ex," going on to say, "You’ve gone after me." When a police aide told Mullen that the cars had to be towed, the email says Mullen wanted to know who was getting a ticket before he provided tow information.

The email concludes with Lutt saying he found "Mullen’s behavior to be inappropriate, to say the least. There was no reason to identify himself as a police officer, except to intimidate the officers on scene and gain control of the conversations and impede the investigation."

What they're saying:

"They were concerned that his behavior was not in line with what a law enforcement officer should be doing and this is why they sent the email," Chandler Councilman OD Harris said.

Harris has been critical of Mullen’s off-duty actions at a protest in January near Hamilton High School where he showed up masked and armed with a gun, telling police it was his plan to let students assault him. Mullen is seen on body camera footage saying, "My plan is legitimately to just let them all assault me and you guys arrest them all, and I will keep it on film and I also have other people filming from a distance, so my goal would be to get all these kids in jail if they want to break the law."

"This guy does not deserve to wear a badge. He’s a disgrace to the badge," Harris said.

Phoenix police fire sergeant over protest conduct

Phoenix Police Chief Matthew Giordano fired Sgt. Dusten Mullen following a controversial encounter with student protesters in Chandler. (5/14/26 report)

After that crash investigation in 2025, Chandler police notified the Phoenix Police Department Professional Standards Bureau about Mullen’s conduct. Phoenix Police Commander Mercedes Fortune provided a statement to FOX, saying the bureau "reviewed all available materials, including reports, body-worn camera footage, and witness accounts. Although concerns were documented by Chandler officers, the review did not establish a policy violation under Phoenix Police Department standards. Sergeant Mullen was not a party to the collision and arrived after the incident. The inquiry has been closed."

Mullen’s attorney, Steve Serbalik, also responded to FOX, saying "in the earlier case, that matter was thoroughly and fairly investigated, Sgt. Mullen answered all questions asked by the professional standards' bureau, and there was no finding of misconduct. This was the correct result in that matter."

Harris does not agree. "How many chances do you give a person to violate public trust?" he asked.

However, Harris does agree with Phoenix Police Chief Matt Giordano’s decision Thursday to fire Mullen for his actions at the Chandler protest. 

What's next:

Meanwhile, Mullen has an ongoing lawsuit against the city, specifically Giordano. He is accusing the chief of fast-tracking the internal investigation and retaliating against his right to protected speech. There is a hearing in federal court on Monday. May 18 at 3 p.m.

Full statement from the Phoenix Police Department

"The Chandler Police Department submitted the 2025 incident to our professional standards bureau for evaluation. The bureau reviewed all available materials, including reports, body‑worn camera footage, and witness accounts. Although concerns were documented by Chandler officers, the review did not establish a policy violation under Phoenix Police Department standards. Sergeant Mullen was not a party to the collision and arrived after the incident. The inquiry has been closed."

Full statement from Steve Serbalik, Mullen's attorney

"Sgt. Mullen believes there are significant differences between allegations of misconduct and sustained violations of misconduct. In the earlier case, that matter was thoroughly and fairly investigated. Sgt. mullen answered all questions asked by the professional standards' bureau, and there was no finding of misconduct. This was the correct result in that matter."