Security volunteer ordered to stand trial in accidental shooting of Utah No Kings protester 

The armed volunteer accused of killing an innocent bystander at a Salt Lake City No Kings protest in 2025 has been ordered to stand trial for manslaughter, a second-degree felony. 

Third District Judge Derek Williams made the ruling at the conclusion of a preliminary hearing Tuesday, said Keith Chalmers, spokesperson for the Salt Lake County District Attorney’s Office.  

Prosecutors say Matthew Scott Alder, 43, of Murray, was aiming at a man carrying a rifle when he mistakenly shot Arthur “Afa” Ah Loo at the demonstration last year. They allege Alder committed a crime with one “reckless” gun shot that struck Ah Loo, of three total that he fired. 

The judge’s decision comes ahead of a new round of No Kings protests scheduled for Saturday across the country, including multiple events in Utah, to be held in opposition to President Donald Trump’s policies and rally voters ahead of the midterm elections. 

It also followed testimony in court Tuesday from other protest volunteers and argument from Alder’s defense lawyer that he did not act recklessly, KSL.com reported. His attorney Neal Hamilton entered a plea of not guilty on his client’s behalf and did not immediately respond to a request for comment Tuesday evening. 

Ah Loo, a 39-year-old father of two, a fashion designer and the first Samoan contestant on TV’s “Project Runway,” had been marching with fellow demonstrators on State Street and taking video when he was shot. 

Alder told investigators he believed he saw a man “ducked down as he was loading his rifle” and who he thought was about to commit a mass shooting, charging documents say. He’s accused of firing at the man, toward a crowd. 

Salt Lake City police initially arrested the man with the rifle for investigation of murder, saying the volunteer saw him manipulating his gun. He was also shot and wounded, but was later released and has not been charged with any crime. Openly carrying a firearm, including at crowded events like protests, is allowed under Utah law.

In response to a pending lawsuit filed by widow Laura Ah Loo and other family members, attorneys for Alder have argued in a court filing that the demonstrator seen carrying a rifle is to blame for what happened that day.  

1 year on, widow of bystander killed at No Kings protest calls for ‘responsible gun laws’

As Afa Ah Loo’s community and family mourned his death, the events shined a spotlight on Utah’s permissive gun laws and raised questions about who’s responsible when a bystander is killed at a public event. Measures brought by Democrats to clarify that responsibility and restrict guns at protests failed in the overwhelmingly Republican state Legislature this year. 

Organizers of the 2025 march have also come under scrutiny for its use of armed volunteers at the event, leading the national 50501 organization to cut ties, and for the information it provided in its event permit application to Salt Lake City.

Alder returns to court for a pretrial conference on Dec. 11.