(PORT HURON) — A judge has revoked the bond of a Fort Gratiot man who pleaded guilty in the death of a tow truck operator, after he violated terms of his bond. 18-year old Trent Sheldon was taken into custody following a hearing Monday in St. Clair County Circuit Court. Reports say that lab tests showed varying amounts of the active chemical THC, which is found in marijuana, in samples taken from Sheldon between February 18 and April 8. Conditions of bond stated the prohibited use or possession of any controlled substance and random drug screenings twice a week. Sheldon pleaded guilty in March to the death of Jason Schultz, owner of Preferred Towing. The crash occurred the morning of January 15 at the intersection of North and Keewahdin Roads in Clyde Township after Sheldon attempted to pass the stopped tow truck on the right side of the road, striking Schultz. Authorities say the emergency lights were activated on Schultz’s tow truck when the crash took place. Toxicology reports also showed that Sheldon had marijuana in his system at the time of the crash. His sentencing has been moved from May 19 to Friday, April 29 at 10 a.m.