Birchfield was last seen leaving his residence on Stoneybrook Drive in Richmond County, Georgia on September 20, 1991. He was accompanied by two unidentified men at the time. Birchfield has never been heard from again. He left his wallet behind, inside his home.

Birchfield was caring for his roommate's elderly mother at the time of his disappearance. She died two weeks later. His family has said it is very uncharacteristic of him to vanish and not attempt to contact loved ones. Authorities believe it is possible Birchfield disappeared on purpose to prevent his family from having to watch him die as a result of his terminal illness. A relative reported Birchfield as a missing person in 1993, two years after he was last seen.