Justin Hamrick, 25, has been charged with two counts of failure to comply with mandatory reporting laws.
According to investigators, Hamrick was at a birthday party in June 2011 when his mother told him that his father, Scott Hamrick, had been sexually abusing his stepsisters for the past five years.
Justin Hamrick reportedly told his mother to alert police, but she did not do so, investigators said. He spent the next weeks talking to his brothers, who had also been told of the alleged abuse. He finally called police when his older brother said he himself would call if Justin Hamrick would not.
"Our mandatory reporting laws exist to help protect our children," said Pierce County Prosecutor Mark Lindquist in a written statement. "Law enforcement officers in particular are expected to follow our laws."
According to court documents, the Hamricks have three adult sons and also adopted five girls, who are now between 12 and 21 years old.
Four of the daughters said they'd been sexually abused by Scott Hamrick, and three said they'd been physically abused by his wife, Drew Anne Hamrick.
Scott Hamrick, a 27-year veteran of Central Pierce Fire & Rescue who resigned in June after the abuse investigation began. He took his own life on June 30.
Drew Anne Hamrick pleaded guilty to three counts of tampering with a witness and one count of unlawful imprisonment, and was sentenced to a year in prison.
Prosecutors allege the woman repeatedly hit the girls at their home in Eatonville, locked up them up without food for days at a time, and made them promise not to tell anyone about the sexual abuse.
One girl told investigators Drew Anne Hamrick often locked her in her room with a padlock and kept her inside for several days without food.
The girl also was made to sleep on the room's concrete floor on which she was also forced to defecate. She was initially given a bucket for this purpose, but the bucket was later taken away, she said. Drew Anne Hamrick also kept her puppies in the same room, and the dogs also relieved themselves on the floor, the girl told investigators.
At one point, the girl began sneaking away to a neighbor's home for food and water, detectives said, but when the Hamricks found out, they screwed her windows closed and put plywood over the glass.
The same girl, who is now 14, told investigators Scott Hamrick began sexually abusing her when she was 5 or 6 years old, and continued to abuse her until earlier this year.
Another daughter told detectives Scott Hamrick began sexually abusing her "ever since I can remember," and when the sex abuse allegations surfaced, Drew Anne Hamrick told her, "Why do you hate your dad? It's not like he raped you ... he just touched you." The couple made her promise not to tell anyone, she said, and Scott Hamrick, amid tears, told her he'd kill himself if she did.
A third daughter, who is now 21, said Drew Anne Hamrick "slashed" her with scissors when she was 14 years old, and then used tape to close the wound, the statement said. She added she had a burn on her arm from the time Drew Anne Hamrick threw a hot curling iron at her. The woman and another daughter reported having been beaten with a metal spatula by Drew Anne Hamrick.
Justin Hamrick is scheduled to be arraigned on Dec. 24.