Two sex offenders plead guilty to possessing child pornography

SEATTLE - In two separate cases, registered sex offenders have pleaded guilty in federal court to possession of child pornography, according to federal prosecutors.

Jonathon Umphlett, 31, of Arkansas pleaded guilty Wednesday in U.S. District Court in Seattle and is scheduled to be sentenced on Jan. 13, 2021.

Michael David Mathisen, 68, of SeaTac, Washington, pleaded guilty on Oct. 9 and is scheduled to be sentenced on Jan. 8, 2021.

Since both men have prior convictions for sex offenses, they face a mandatory minimum of 10 years in prison, according to U.S. Attorney Brian Moran.

Seattle police made contact with Umphlett in June after a person at a restaurant said he was viewing what appeared to be child pornography on his smart phone, Moran said. Detectives detectives verified that his phone contained images of children engaged in sexually explicit conduct, Moran said.

Umphlett has a 2014 conviction in Arkansas for sexually assaulting a 7-year-old boy, officials said.

Mathisen was arrested after Microsoft contacted the National Center for Missing and Exploited Children to report an account linked to Mathisen was uploading images and searching the internet for images of children engaged in sexually explicit conduct.

A search of Mathisen’s electronic devises found 19 files containing child pornography, Moran said. He has convictions in 1984 and 1994 for molesting children under the age of 9.