This article contains plot spoilers for the 2017 series of Twin Peaks.
Detective Don Harrison was a detective with the South Dakota State Police.
Harrison oversaw the interrogation of William Hastings in relation to the murder of Ruth Davenport and the unidentified male found in her apartment. He later went with Detective Dave Macklay to search Hastings' home and car, finding a piece of flesh in the latter.
Constance Talbot later revealed to Harrison and Macklay the cause of death for the John Doe was decapitation. She then showed them a ring found inside the body, inscribed: "To Dougie, with love, Janey-E."