Investigators are working to determine what happened to 27-year-old Adrienne Martin, who was found dead earlier this week in the St. Louis-area mansion of August Busch IV, the heir of the Anheuser-Busch dynasty.

In 1983, when Busch was 20, he was involved in a car accident in which his friend and passenger, Michele Frederick, 22, died. According to published reports at the time, Busch, who was then a sophomore at the University of Arizona, had been driving a black Corvette 20 miles above the posted speed limit when the car spun out of control.

Busch left the scene and cops later found him with a severe head wound at his home in Tucson. Busch was never charged due to lack of evidence.