A convicted sex offender is in trouble again. A Reno man released from prison following a child sexual assault conviction in 2004, is charged with possession of child porn.. 51 year old Robert Gupton, was arrested after a cyber tip from the National Center for Missing and Exploited Children of a transmission of possible child sexual abuse material. Through their investigation over several months, detectives identified Gupton as the suspect. Gupton faces two felony charges.