Fall City murders teen suspect not arraigned Friday as prosecutors request move to adult court

The King County Prosecuting Attorney’s Office (KCPAO) announced Friday that it will amend the domestic violence designations for several charges in the case of a 15-year-old boy accused of killing five family members and attempting to kill a sixth.

This came after the teen suspect was taken into custody Monday.

During Friday’s appearance, the judge ruled the teen’s face may not be shown and his name cannot be used.

On Thursday the King County Medical Examiner’s Office identified those victims as 43-year-old Mark Humiston, 42-year-old Sarah Humiston, 13-year-old Benjamin Humiston, 9-year-old Joshua Humiston, and 7-year-old Katheryn Humiston.

The teen faces five counts of first-degree aggravated murder and one count of attempted first-degree murder.

Initially, all charges included a domestic violence designation based on Washington state’s definition of “family or household members.”

Upon further review in the Friday hearing, prosecutors determined that under Washington law, the domestic violence designation only applies to adult family or household members and does not cover relationships between child siblings.

As a result, prosecutors are removing the domestic violence designation from three aggravated murder charges involving the teen’s siblings and the attempted murder charge involving an 11-year-old sister who survived.

The amended charges will still proceed without the designation.

The KCPAO also noted that removal of the domestic violence designations will not affect the sentencing range if the teen is convicted.

Prosecutors are also requesting that the case be moved to adult court, a process known as declining juvenile jurisdiction.

If transferred to adult court and convicted, the teen would face a sentence of 25 years to life, with the potential for release after 25 years, subject to review by the state’s Indeterminate Sentence Review Board.

If the case remains in juvenile court, the maximum sentence would be confinement until age 25, then he would be released.

An arraignment will not take place until the decision of adult or juvenile court is decided. That decision will be released in a hearing on June 4, 2025.

The state prosecutors say this will not be a case they quickly go through, as there is a mountain of evidence already.

“There are well over 1,200 photos that were taken by Washington State Patrol crime lab. There are already a great number of reports that we are going through in the next couple of days that will all be processed and made available,” said the prosecutor.

Before court adjourned on Friday, the suspect’s attorney spoke on behalf of the teenager.

”Many people have reached out to us who know (the suspect), they have attested to his good character, he has been described as kind and caring, someone who has friends and engages in social activities, someone who has been a positive contributor to his community,” the defense attorney said.

A status hearing for the case is set for January 8, 2025.