Callahan was killed in a vehicle crash, along with the driver, Michael Hager, after the Vanagon in which they were riding crashed into a pair of trees on U.S. Route 58 West around 1:30 PM on June 26, 1995. Neither man was wearing a seat belt, which likely contributed to each of their deaths. Found with Callahan's body were two scalped Grateful Dead tickets, a dollar in quarters, and a yellow Bic lighter. A letter was found, depending on sources either in Callahan's pocket or near the crash site, reading: "Jason, Sorry we had to go, see ya around, call me #914-XXXX. Caroline T. & Caroline O. Bye!!!!". The phone number on the letter lacked an area code and never led to any additional clues. The letter also contained a small drawing that some speculate may be of Jerry Garcia. The tickets were dated June 24, 1995, and June 25, 1995, respectively; the Grateful Dead performed at the Robert F. Kennedy Memorial Stadium in Washington, D.C., on these dates. Authorities were able to trace the tickets to a Pennsylvania man, but the man turned out to be a ticket reseller and could not recall the details of who he sold them to. Neither of the 'Carolines' have ever been identified.
