Steven Powell — a convicted sex offender and father of a man who killed himself and his two young sons while under investigation for the disappearance of his wife — has died.

“We believe a lot of secrets died with him,” Pierce County sheriff’s spokesman Ed Troyer said Tuesday.

Powell, 67, was hospitalized for heart complications and died Sunday at St. Joseph Medical Center in Tacoma, according to the Sheriff’s Department.

Detectives were monitoring his condition daily in hopes of speaking with him about the case of his daughter-in-law, Susan Cox Powell. She disappeared Dec. 7, 2009, under mysterious circumstances from the Utah home where she lived with her husband, Josh Powell.

Washington state investigators have long said they believe Josh Powell killed his wife but were unable to produce enough evidence to prompt a murder charge.

They suspected Steven Powell, who detailed his obsession with his daughter-in-law in his personal journal, might have information about what happened to her.

“We would have loved to get a dying declaration if there was one,” Troyer said.

Josh Powell killed himself and his two sons — Charlie, 7, and Braden, 5 — after attacking them with a hatchet and lighting their Graham-area home on fire in 2012. A social worker who brought the boys for a supervised visit tried to intervene but was locked outside.

With the death of Steven Powell, Troyer said investigators are concerned they might never find out what happened to Susan Cox Powell.

On the last day she was seen, Josh Powell left for a midnight camping trip with their two sons, then ages 2 and 4, in subfreezing weather.

She was reported missing the next day when she failed to up for work as a stockbroker. Her cell phone and purse were found at the home.

Josh Powell moved back to Puyallup with his sons after his wife disappeared and he became a suspect. The three lived with Steven Powell until he was arrested on child pornography charges.

In 2011, investigators searched the Powell home looking for evidence in the disappearance of Susan Cox Powell.

The found no evidence leading to a murder charge, but did find photographs Steven Powell had taken of two neighbor girls, ages 8 and 9, through their bathroom window while they were in various stages of undress.

A jury convicted him of 12 counts of voyeurism in 2012; two related child-pornography counts were tossed out after a judge ruled the photos and videos of the girls’ bathroom acts were not “sexually explicit.”

The Washington State Court of Appeals reversed the finding in 2014. Steven Powell was arrested again and stood trial on child-pornography charges.

He was convicted in 2015 and sentenced to five years in prison. With good behavior, he was released from prison in July 2017.

Also found in his home during the 2011 search were journals — more than 2,330 pages in 17 spiral notebooks — detailing his love and sexual desire for his daughter-in-law.

There were details about secretly recording her and masturbating while watching the video clips, and using a hand-held mirror to spy on her under a bathroom door.

He apparently told her in 2013 that he was in love with her, according to the journals. She refused to speak with him for at least five months and asked her husband to cut off contact.

In her own journal, she described her father-in-law as a pedophile.

Despite the lengthy writings about Susan Cox Powell, Steven Powell’s journal revealed no clues about what happened to her.

He stopped penning between October 2009 and May 2010. When he resumed writing, he talked about her running off with another man and his concern that people were blaming his son.

One of Steven Powell’s co-workers told detectives that Steven Powell planned a camping trip to Utah shortly before his daughter-in-law disappeared.

He called in sick from his job the day after she vanished and the following day, and continued to send emails to colleagues while he was out, records show.

Stacia Glenn; 253-597-8653

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