Robertson was reportedly handicapped, "required special care for his condition," and was "unable to take care of himself on a daily basis."
The Sheriff's Office observed the inside of the home was "extremely filthy and unkept."
Investigators believe Robertson's caretakers, Michael Hammond, 46, and Lauri Parker, 59, primarily kept him confined to one room in the basement of the home. The door was reportedly designed to lock from the outside, "thereby containing Mr. Robertson within this particular room."
The Sheriff's Office alleges Hammond and Parker had "neglected their duty to care for Mr. Robertson in a manner required by law."
The Sheriff's Office announced the arrest of Hammond and Parker Tuesday, June 13, and they were charged with neglect of a disabled adult. Additional charges may be filed following the autopsy report and investigation into Robertson's death.
According to the Sheriff's Office, investigators said it was one of the "worst cases of neglect that they have seen," and they described Robertson's living conditions as "horrific."