A 24-year-old Phoenix woman is now facing a manslaughter charge after a Central Phoenix road-rage confrontation on Sept. 27, 2025 ended with a man fatally shot. A grand jury indicted her last week, and she was taken into custody on Tuesday with bond set at $500,000. The victim, 54-year-old Stephen Guardino, died the day after the shooting.
Indictment and Booking
According to Arizona’s Family, a Maricopa County grand jury indicted Heather Arriaga on a single manslaughter count in connection with Guardino’s death. Prosecutors said the indictment was returned on April 2. Arriaga was arrested and booked into jail on Tuesday, where a judge set her bond at $500,000.
What Police Say
In a media advisory, Phoenix police said officers were called just after 2 p.m. to the intersection of 7th Avenue and Missouri Avenue. They arrived to find an adult man with a life-threatening gunshot wound; he was taken to the hospital and later died. Detectives say Guardino got out of his vehicle and walked up to a woman in another vehicle that was stopped at the light. According to the advisory, the woman remained at the scene after the shooting and was interviewed by investigators.
Witness Accounts
People who saw the encounter described a fast-escalating confrontation. Malasia Williams told ABC15, “He spit on her, and she shot him,” adding that the incident unfolded in seconds. Other witnesses said bystanders rushed in to perform CPR on Guardino before first responders arrived. Several people at the scene also said the two SUVs involved had been driving aggressively just before the clash.
Legal Next Steps
The grand-jury indictment formally charges Arriaga and sends the case into county court for arraignment and pretrial hearings. Under Arizona law, manslaughter is defined in ARS 13-1103 as a Class 2 felony and can carry years in prison, according to legal summaries of the statute.
Broader Context
Investigators and local reporters say this case is part of a troubling trend. A statewide review of crash data found that road-rage-related crashes roughly doubled between 2020 and 2024, according to an investigation by Arizona’s Family. Hoodline first covered the September shooting last year as residents in the neighborhood reacted, and this new indictment is the first public criminal filing tied to the case.
Arriaga remains in custody on the $500,000 bond, and court records have not yet listed a public arraignment date. Phoenix police say the investigation is ongoing and are asking anyone with video or additional information about the incident to contact detectives.
