Ted S. Warren / AP
Steve Powell looks toward his attorneys during the day of final arguments in his voyeurism trial, Tuesday, May 15, 2012, in Tacoma, Wash.
TACOMA, Wash. -- A jury found Steven Powell guilty Wednesday on 14 counts of voyeurism for taking pictures of girls and women in various states of undress for the purpose of sexual gratification. The charges stemmed from an investigation into his missing daughter-in-law.
Defense attorneys had argued that there was too much reasonable doubt in the case to convict Powell, but jurors disagreed, finding him guilty on all counts.
Powell is the former father-in-law of Susan Powell, who has been missing since December 2009. Her husband, Josh Powell, who is Steven's son, was a person of interest in her disappearance. He killed himself and the couple's two children in an explosion in Graham, Wash., earlier this year.
Steven Powell's sentencing hearing was scheduled for June 15. He faces a standard sentence of about four years, but the state has alleged aggravating factors that could result in a longer term.
Authorities brought the voyeurism charges last year after searching Steve Powell's home during their investigation into the disappearance of Susan Powell in Utah.
Jurors questioned evidence during deliberations, asking if a disc of pictures was found in boxes containing only Steve Powell's belongings.
Evidence used by prosecutors included photos of young girls in bathrooms, girls changing clothes and at least one video of Powell allegedly touching himself. The photo corresponding to each charge was shown once again to jurors during the prosecution's closing arguments.
Defense attorneys argued reasonable doubt exists and that, "this case is not about what you feel, it's about what you know."
The photos were found on Powell's computer last fall when police searched his Puyallup home. At the time, Powell's former daughter-in-law, Susan Powell, had been missing for nearly two years. Officers were looking for her journals.
A child pornography charge against Steven Powell was thrown out last week.
Photos of Susan Powell were tossed out as evidence because she was not considered one of the alleged victims in the voyeurism case.
King 5-TV and msnbc.com staff contributed to this report.
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