Utah Judge Advances Matthew Alder Manslaughter Case

• A Utah judge found probable cause to advance a manslaughter case against Matthew Alder.
• Alder, a volunteer safety team member, fatally shot protester Arthur Ah Loo during a June 2025 No Kings protest in Salt Lake City.
• Alder fired at Arturo Gamboa, who was armed and masked, believing he was preventing a mass shooting.
• The defense suggested a ricochet caused Ah Loo's death, while the prosecution argued Alder fired recklessly into a crowd.
• Judge Derek Williams cited the presence of multiple people between Alder and Gamboa when ruling for probable cause.

Third Judicial District Judge Derek Williams ultimately concluded that the state had presented sufficient evidence to establish probable cause for the manslaughter charge.

On June 14, 2025, a No Kings protest in downtown Salt Lake City, Utah, became the scene of a fatal shooting. Matthew Alder, a volunteer safety team member present at the event, discharged his firearm three times, targeting a man he perceived as an imminent threat. Alder later stated to police that he believed this individual, identified as Arturo Gamboa, was preparing to unleash a "mag dump" into the assembled crowd of protesters. Gamboa was observed dressed entirely in black, wearing a ski mask, and carrying a rifle, which he was reportedly assembling from a bag behind building columns.

Alder's shots struck Gamboa, causing injury to his left abdomen, but tragically, one of the rounds also hit and killed protester Arthur "Afa" Ah Loo. The situation was described by Salt Lake City Police Officer Bradley Shupe as chaotic. Other safety team members, including Nathan Berkstrom and Aaron Ferdig, testified about an anxious atmosphere, noting the presence of agitators and counterprotesters, referred to as "chuds," who drove around and brandished weapons. Berkstrom, who was unarmed, recounted seeing Gamboa acting in a "clandestine manner" and believed he was about to commit a mass shooting, prompting him to radio other team members. Ferdig echoed these concerns, questioning why someone would be assembling a rifle in concealment at the protest's conclusion. Despite safety team members being discouraged from carrying weapons, Ferdig chose to bring a handgun due to the heightened risk, citing the assassination of two Minnesota state lawmakers that same morning. Gamboa ultimately fled the scene, discarding his clothing, mask, and rifle, and was later arrested by police after protesters directed officers to his location.

Following the incident, Salt Lake County District Attorney Sim Gill filed manslaughter charges against Matthew Alder last December. During a recent probable cause hearing, Alder did not provide testimony. His defense attorneys, led by Neal Hamilton, presented an argument suggesting that the fatal shot that struck Arthur Ah Loo might have been a ricochet. They cited new forensic evidence and an autopsy report, contending that the investigation's conclusion of no ricochet indication was inaccurate and that evidence pointed to "something intervened and caused it to tilt and travel at an angle."

Conversely, Deputy District Attorney Josh Graves argued that Alder's actions constituted reckless firing, especially given the backdrop of numerous protesters. Graves emphasized that each pull of the trigger represented a "conscious decision" by Alder, reserving the discussion of self-defense justification for a later stage. Third Judicial District Judge Derek Williams ultimately concluded that the state had presented sufficient evidence to establish probable cause for the manslaughter charge. Judge Williams highlighted that the firing was "in the direction of a crowd of people" and noted evidence indicating "at least three, if not four, people" were positioned between Alder and Gamboa at the time of the shooting. Officer Shupe confirmed that the third shot was the one that struck Ah Loo, causing him to immediately fall.

The decision by Third Judicial District Judge Derek Williams to advance the Matthew Alder manslaughter case provides a critical illustration of the legal standard for probable cause, particularly in the complex realm of self-defense claims arising from chaotic public events. This ruling signifies that the prosecution has met the initial burden of demonstrating a reasonable belief that a crime was committed and that Alder was the perpetrator, allowing the case to proceed to trial. The judge's focus on the trajectory of the shots, specifically that they were directed into a crowd, underscores a key element of the prosecution's argument regarding recklessness.

This case highlights the challenges faced by both criminal defense attorneys and prosecutors in establishing intent and causation within a highly charged and confusing environment. While Alder's perception of a mass shooting threat informed his actions, the court's initial assessment prioritized the objective danger posed by firing a weapon into a populated area. The defense's "ricochet defense" introduces a complex forensic question about the precise mechanism of death, but at the probable cause stage, the court weighed the overall circumstances of the shooting, including the presence of innocent bystanders, as central to the determination of potential criminal liability.

This case provides a critical example for criminal defense attorneys and prosecutors regarding the standard for establishing probable cause in complex self-defense claims, particularly in chaotic public protest environments. It highlights the challenges of proving intent and causation (e.g., ricochet defense) and the judiciary's focus on reckless firing even when a perceived threat exists.

Source: Original reporting via Courthouse News.