Riley was last seen at the Riverlands Health Care Center, a nursing facility in Lutcher, Louisiana, on February 6, 1990. He'd been living there four about nine months. He got dressed and tried to leave the nursing home between 5:00 and 4:30 a.m., but the staff found him and made him go back to his room. When they checked between 4:45 a.m. and 5:00 a.m., he was gone and the staff notified the police. An extensive search of the area turned up no sign of Riley, however; he has never been heard from again.

Riley frequently took walks or rode his bicycle in the community prior to his disappearance. There were no sightings of him in the local community in the days after he vanished, however, so police don't believe he's still in the area. His case remains unsolved.