Monday night, the Kane County state's attorney was convening a grand jury to investigate the incident.
The hunt is part of an annual tradition among St. Charles North high school students, but the Kane County states attorney says he wants to investigate the incident and try to get to the bottom of what happened. He admits it is possible there was no crime involved.
Investigators say they believe there were dozens of witnesses, but that apparently includes none of the few neighbors who live on the street where late Friday night a 17-year-old jumped from the moving vehicle.
The teen's identity has not been released.
Approximately, 70-100 teenagers took part in the scavenger hunt that included challenges or dares, many of them dangerous. One of the items on the list was to have a person jump from a moving motor vehicle moving at 25 miles per hour.
The driver says she planned on taking a photo of the speedometer, but she stated she planned to slow down to 10 or 15 miles an hour. She stated the boy jumped from the vehicle without giving her any notice.
Police found the 17-year-old in the middle of the street and transported him to a hospital.
The state's attorneys office plans to use a grand jury to subpoena witnesses, as they did four years ago after a deadly brawl. They say that is the best way to compel reluctant witnesses to tell what they know about what happened.
The teenager was listed in critical condition Monday night.
St. Charles North high school is making counselors available, but representatives also say the school was in no way involved in the planning or in any other aspect of the scavenger hunt.