The Office of the Chief Medical Examiner in Chapel Hill said in a report made public Tuesday that Silliman's body was found in a Coleman sleeping bag.
"The sleeping bag is removed to reveal a clear plastic bag over the head held in place by two connected white plastic ties around the neck, and a loose clear plastic bag over the feet. The plastic bag over the feet is removed to reveal two connected white plastic ties binding the ankles, over the pants and socks. Two interlocked white plastic ties bind the wrists in front of the body, over two pairs of gloves. The clear plastic bag over the head is removed to reveal dark colored duct tape in place over the mouth," reads the report.
The report also says Silliman had writing on his arms.
"On the right medial forearm there is a partially indiscernible message which reads "I Love (indiscernible word)." On the left medial forearm is a partially indiscernible message written in black ink and pink discoloration consistent with ink which reads "(indiscernible words) fail." There also appears to be a cross-shaped symbol on the left medial forearm in black ink outlined by similar pink discoloration or ink."
The report says Silliman had wounds to his scalp, but that was not the cause of death. It says he had a large amount of an anti-depressant drug in his system and he was strangled/suffocated.
"Given the autopsy and investigative findings, it is our opinion that the cause of death in this case is asphyxiation. The concentration of bupropion is potentially lethal, and along with acute ethanol intoxication, likely played a role in respiratory depression and sedation prior to death from asphyxiation due to ligature strangulation/suffocation."
The four teens accused of involvement in Silliman's death could face life in prison if convicted. According to Silliman's Facebook page, the suspects were all his friends. Dahlquist and Kahn attended Apex High School with Silliman. Shaw was enrolled at Panther Creek High School, while Hare withdrew from the same school last February.
Silliman was first reported missing by his parents on Nov. 26 and authorities had issued a Silver Alert for him. He was last seen less than 10 miles from the crime scene.