Mother of slain autistic teen charged with covering boyfriend’s alleged abuse

An Auburn woman was charged Tuesday with rendering assistance to her boyfriend, who is to stand trial in December on murder and assault charges.

Former Renton School District special-education teacher Pascia Backman, 42, was charged with first-degree rendering criminal assistance in connection with the April 2014 death of her severely autistic son, 18-year-old Otto Smith, court papers read. She also was charged with second-degree rendering criminal assistance for the abuse allegedly sustained by her younger son, according to the charges.

Backman’s boyfriend, Matt Christenson, 43, was charged in January with second-degree assault and second-degree unlawful imprisonment in connection with the younger boy, who was 14 when Christenson moved into the family apartment in January 2014, charging papers read. He was charged with second-degree murder in March and remains jailed in lieu of $1.5 million bail.

A summons has been issued for Backman’s arraignment Oct. 13 in Kent, said Dan Donohoe, King County prosecutor spokesman. Backman is accused of destroying evidence, and lying to hospital staff and medical investigators to cover up Christenson’s alleged crimes against her children, court papers read.

In August 2014, four months after Smith died, Backman, Christenson and Christenson’s 20-year-old son were each charged with first-degree malicious mischief after allegedly trashing their apartment, court records read. At that time, Backman told an officer she thought the apartment was haunted, according to court documents.

In December, Backman was taken by ambulance to Tacoma General Hospital, where she claimed to be a kidnapping victim, court documents read. Doctors connected her with a social worker, who reported that Backman told her Christenson “had killed her 18-year-old autistic son and she (Backman) had helped clean up evidence,” the papers say. The social worker reported the information to police, who opened an investigation into the death, according to the charges.