On the evening of June 19, 1986, Stanley and his wife, Susan, were arguing about his drinking problem. He drove Susan, his five-year-old daughter, Seleste, and his one-year-old son, Chad, to a remote area outside Cottonwood. Stanley and Susan continued to argue as they sat in the car. Stanley ended the argument by shooting Susan three times in the head. He then shot Seleste once in the top of the head, pressing the muzzle of the gun into the skin. Stanley did not shoot Chad because the boy was too young to tell what he had seen.
After dumping Susan's and Seleste's bodies off the side of the road, Stanley went home and put Chad to bed. Several hours later he called the police and told them that Susan and Seleste were missing. The police began a wide-ranging search that ended late the following day when Stanley confessed. Stanley received the death penalty for the murder of Seleste and a life sentence for the murder of Susan.