Ex-cop who shot and killed wrong man sues Glendale for firing him

In January 2025, Glendale police officers were searching for a domestic violence suspect when they located 46-year-old Dillon Siebeck in a city park. Despite Siebeck not matching the description of the suspect — a 23-year-old Latino man — officer Juan Gonzales shot and killed him.

On Dec. 31, the killing resulted in a wrongful death suit from Siebeck’s family against Gonzales, his supervisor and the city. Glendale also fired Gonzales in July, though the city did not reveal the firing until nearly six months later, when the lawsuit was filed. Gonzales appealed his termination to the city’s Personnel Review Board, which voted to reinstate him, but the interim city manager overruled that recommendation and sent Gonzales packing. Gonzales had been with the department since 2014.

Now the city is getting hit with a second lawsuit over the shooting, although this time it’s Gonzales suing to get his job back. On Jan. 9, attorneys for Gonzales filed suit against the city in Maricopa County Superior Court, asking a judge to reinstate him as a police officer and award him back pay and other damages. 

The city declined to comment, citing active litigation. Neither Gonzales nor the law firm representing him — Yen Pilch Robaina & Kresin — responded to Phoenix New Times’ request for comment. 

Central to Gonzales’ claim are the findings of the review board hearing, which conducted three hearings on his termination in October and November. Gonzales’ case was the only item on the agenda for all three hearings. The first two, which occurred on back-to-back days in mid-October, lasted a total of nearly seven hours. The final meeting on Nov. 7, in which board members voted 3-0 to “not sustain” the city’s decision to terminate Gonzales, lasted nearly eight hours.

Per Gonzales’ lawsuit, the board found that “the City did not have just cause to take disciplinary action against Gonzales based on the stated violations of the City’s human resources policy.” New Times has requested documents related to the personnel board’s decision but has not received them.

During the Nov. 7 meeting, board member Jeff Rosenberg said that “the policies were a little bit vague and open-ended ended and I’m not sure there was enough evidence presented that there wasn’t just cause” for the shooting. “You gotta think of what’s going on in that moment. You’re surrounded by 15 other officers or whatever it was. And nobody said, ‘Don’t do that.’”

Indeed, the lawsuit filed by Siebeck’s family members also names Gonzales’ supervisor, Sgt. Joshua Anderkin, in the lawsuit. That suit blames Anderkin for not stopping Gonzales from shooting, noting that 14 seconds passed between Gonzales’ first shots at Siebeck and his next volley, which killed the 46-year-old. Anderkin remains with the department.

Termination upheld

Despite the personnel board’s recommendation, Interim City Manager Kevin Phelps upheld Gonzales’ termination. In a Dec. 8 letter to Gonzales, he wrote that “it is my responsibility to make the final decision following the Personnel Board Hearing. While I appreciate the Personnel Board’s review of this matter, I am upholding the termination.” 

In the letter, Phelps cited disciplinary action against Gonzales from August 2022 that found he “failed to properly handle, display and use your firearm.” He also cited findings from the city’s Response to Resistance Panel “that you acted outside of policy regarding this shooting.” New Times has requested documents from that panel decision but has not received them.

“I believe these incidents demonstrate a pattern that presents a safety risk to our community and your fellow officers,” Phelps wrote in his letter to Gonzales. “Your actions on January 8, 2025, were not within City policy and directly resulted in the death of an innocent victim, therefore, I cannot in good conscience, allow you to resume your duties and responsibilities as a Glendale Police Officer.”

Siebeck was killed when Gonzales and other officers mistook him for Angelo Diaz, a 23-year-old domestic violence suspect. Officers initially located a truck matching the description of Diaz’s and ordered anyone inside to come out, but said they couldn’t see anyone inside because of the truck’s window tint. Then they turned their focus to Siebeck, who was sitting 100 yards away in the park.

According to the lawsuit against the city from Siebeck’s family, officers then yelled at Siebeck — calling him “Angelo” — to put his hands on his head and walk toward them. While an officer was giving those instructions, that lawsuit says, Gonzales fired twice at Siebeck, paused for 14 seconds, and then shot two more times, killing him. The suit claims officers didn’t render aid to Siebeck for nearly 20 minutes. Later, they located Diaz inside the truck, dead from a self-inflicted gunshot wound.

“(Siebeck) was unarmed and did not present any type of threat to the officers. He was not a suspect in a crime and was minding his own business,” said Antonio Romanucci, the family’s attorney, in a press release about the lawsuit. “Dillon’s loss of life was completely needless. We will pursue full accountability for what happened that evening in Glendale.”

Romanucci’s firm declined a request for comment on Gonzales’ lawsuit. 

The Peoria Police Department investigated the shooting and turned over its findings to the Maricopa County Attorney’s Office, Glendale city spokesperson Jose Santiago told New Times in a statement last week. But the county attorney’s office declined to pursue charges, and Gonzales wasn’t prosecuted.

Nonetheless, Gonzales was terminated in July, leading to his appeal, the personnel review board hearing and the city manager’s decision.