A new KIRO 7 video published June 23 revisits the Fall City killings and the long-running court fight over whether the 15-year-old charged in the case will be tried as an adult. The Oct. 21, 2024 shooting killed two parents and three children and left an 11-year-old wounded, and it has since become a tangle of disputed forensic findings, competing legal filings and repeated scheduling delays.
Investigators identified the victims as Mark and Sarah Humiston and three of their children, Benjamin, 13, Joshua, 9, and Katheryn, 7. They say a 15-year-old in the household faces five counts of aggravated murder and one count of attempted murder, as reported by The Guardian. According to court papers, the suspect called 911 early that morning and claimed his 13-year-old brother had shot the family. A neighbor later reported finding an injured 11-year-old who said the older boy was the shooter.
Prosecutors' account
Prosecutors allege the teen took a Glock from a lockbox, systematically shot his parents and siblings, then placed the weapon in the 13-year-old’s hand to stage the scene as a murder-suicide. They say he then showered, changed clothes and called 911 with a false story. Investigators also point to forensic details they argue undercut any suicide theory, including wounds they say are inconsistent with a close-range, self-inflicted shot. Those allegations, along with a summary of the probable-cause affidavit, are detailed by Law&Crime.
Defense response and delays
Defense attorneys counter that missing crime-scene reports, deleted digital evidence and early prosecutorial filings have hampered their ability to finish the psychological and forensic work the court expects before a decline decision. In a recent filing, the defense complained, “The salacious details from the government’s slanderous motion were heavily reported on,” arguing that media coverage has chilled potential witnesses.
Those defense claims, along with prosecutors’ push to move the case to adult court, have fed into a series of postponements, according to reporting by the Snoqualmie Valley Record.
Legal implications
Under Washington law, the judge must hold a discretionary “decline” hearing and weigh eight criteria, known as the Kent factors, before transferring a juvenile case to adult court under RCW 13.40.110. That process requires written findings and an assessment of the youth’s development, background and capacity for rehabilitation. The outcome can shift the defendant’s potential exposure from juvenile custody, which typically ends by age 25, to adult penalties. For background on the decline process and the Kent factors, state officials point to the Washington Association of Prosecuting Attorneys' guide and recent state court rulings.
Community reaction and what to watch
Neighbors and the wider Snoqualmie Valley community have mourned the family and tracked the court filings closely. The victims’ employer described Mark Humiston as a respected colleague, a detail that has underscored the sense of loss in the area.
Prosecutors have amended some earlier charge designations but continue to press for a discretionary decline hearing, while defense lawyers keep asking for more time and more complete records. The key thing to watch now is whether the court finally locks in a firm decline hearing date and whether both sides secure the expert reports and forensic materials judges say they want in hand.
For the moment, the case remains tied up in pretrial motions and scheduling disputes. Judges, prosecutors and defense attorneys will sort out the next steps as additional filings and evidence arrive in the weeks ahead.
