Joseph (played by Paul McLean) was a doctor who practiced at the Grove Medical Clinic in Browning, Montana. In 1994, Joseph attended to Lyle Parker, who had been brought there by Dana Scully to be treated. Joseph also performed tests on Parker.
After Fox Mulder contacted the hospital, looking for Scully, he talked to Joseph, who told him Scully was taking Parker back to his ranch. The doctor also informed Mulder of the results of Parker's blood test, telling him of the discovery of Parker's father Jim's blood type in his blood, something that could "only be there by ingestion".