The autopsy results for country singer Craig Morgan’s 19-year-old son, Jerry Greer, have been released, and the report confirms that he died from drowning during a tubing accident on Kentucky Lake in Tennessee on July 10.

According to The Tennessean, the Humphreys County Assistant Medical Examiner Erin Carney, who conducted the autopsy on July 12, ruled that the death was accidental. The toxicology report showed that Greer tested positive for marijuana and low levels of alcohol in his system at the time of his death.

The teen, who graduated just a few months earlier from Dickson County High School, went missing in the lake when he and his friend were thrown from an inner tube behind a boat. Although Greer was wearing a life jacket at the time, he never resurfaced. The Humphreys County Sheriff’s Department recovered his body the following day, still wearing the life vest.