The father-in-law of missing Utah woman Susan Powell is due to be sentenced in a Washington state court for recording images of two young neighbor girls in their bathroom.

Pierce County prosecutors are asking for an exceptional sentence of 10 years for Steven Powell on Friday. His attorneys are seeking zero to 12 months, saying it's not clear exactly when Powell took the pictures, and it could have been before the state made voyeurism a ranked felony in 2006.

The 62-year-old was convicted last month of 14 counts.

Powell is the father-in-law of Susan Powell, who disappeared from her home in West Valley City, Utah, in late 2009. His son - her husband - Josh Powell killed himself and two sons in a February fire at a home in Graham.