The Seattle city attorney's office revised its complaint against Michael Sean Stanley to accuse him of resisting arrest related to an October incident, and Stanley pleaded not guilty Monday. He was previously accused of harassment and has also pleaded not guilty to that charge.
Stanley's bail is set at $100,000. His attorney did not immediately return a call seeking comment.
Authorities have said they are exploring additional charges against Stanley, saying he may have been involved in a sexual assault of a 16-year-old boy. The King County prosecutor's office is reviewing that case.
Stanley was released from jail in Canada in April 2011 after completing a 32-month sentence for assault and forcible confinement. He was being monitored by police in recent months but cut off his electronic-monitoring bracelet and was able to enter the United States.
Canadian authorities have decided not to seek his extradition.
After Stanley arrived in Seattle, authorities said they had no reason to arrest him but did ask him to register as a sex offender. Then, on Oct. 22, police received several calls reporting noise in an alley and a report that Stanley threatened someone who asked him to be quiet.
When police arrived, Stanley became combative and said he had a knife, according to police. Authorities later said that Stanley had met a boy at a west Seattle grocery store that morning, struck up a conversation and walked with him to an alley where he plied the teen with alcohol. Stanley is accused of grabbing the teen and sexually assaulting him, police said.