A jury found 59-year-old Orcas Island High School teacher Gerald Grellet-Tinner guilty of two counts of Sexual Misconduct in the First Degree.

He was accused of having a sexual relationship with one of his students, who was also his teaching assistant, last October. According to the Washington state legislature, a teacher cannot have intercourse with a registered student under the age of 21 if he or she is at least five years older than the student. The student in this case was 19 at the time of the sexual relationship.

Grellet-Tinner is being held in Island County jail until his sentencing on Aug. 10 at 1:30 p.m. in San Juan County Superior Court. The conviction is a class C felony, punishable by up to five years’ imprisonment, a fine of up to $10,000, or both.