Now, Indiana State Police are trying to find out why he was left there.
Troopers found 18 year old David Halcomb of Clayton, Indiana about 3:30 Saturday morning near mile marker 12 of the eastbound lanes.
Halcomb had a blood alcohol concentration of .12, and he also had a broken leg.
Halcomb and two friends spent the evening in Terre Haute and were on their way back to Hendricks County.
Police believe an argument started in the car, which resulting in Halcomb being left on the interstate. He was taken to IU Health Methodist Hospital for treatment.
Whether he was forced out or left while he vehicle was in motion is still under investigation.
Troopers have tentatively identified the other two involved and will release more information when it becomes available.