Crime Library: Criminal Minds and Methods

Joseph Edward Duncan III


The same day that Steve Groene had made his televised plea for the safe return of his children, sheriff's department investigators and the Kootenai County Coroner's Office released details of the official cause of death of the murder victims. According to the coroner's report, all three victims died from blunt trauma to the head. Each victim suffered skull fractures and contusions of the brain, and investigators believed that a claw hammer may have been the blunt instrument used on each of the bound victims. Following a toxicology analysis, tetrahydrocannabinol, also known as THC, the active ingredient in marijuana, was found in the blood of Brenda Groene and Mark McKenzie. Traces of methamphetamine were also found in their blood. Investigators claimed that they still did not know whether the victims had been killed by one person acting alone or by more than one perpetrator. However, due to the fact that each victim had been bound, they theorized that it may have taken more than one person to subdue the victims and carry out the crimes.

Shasta & Duncan getting in the Jeep
Shasta & Duncan getting in the Jeep

Meanwhile, later that day a tip was phoned in by a sporting goods store owner in Bonners Ferry, Idaho, located about 70 miles north of Coeur d'Alene. The store owner said that a man and two children, a young boy and a young girl, came into his store. The man had asked for directions to Libby, Montana, after which the three left in a white van with Washington license plates. The store owner said that the children fit the descriptions of Shasta and Dylan.

Deputies from Boundary County as well as officers from the Idaho State Police searched the main roads as well as the less-traveled roads that led from Bonners Ferry to Libby, Montana, but there was no sign of the van, the man, or the two children.

As the investigation continued, the cops were still no closer to determining a motive for the crime than they were to finding the children. Drugs, or a drug deal gone bad, had been discussed as one possible motive — except that the house on Frontage Road didn't contain evidence of drugs or of a methamphetamine lab, which were scattered here and there throughout the Pacific Northwest, despite the fact that marijuana and methamphetamine were found in Brenda and Mark's blood during their autopsies. To the cops it looked more like they had just been recreational users and had likely used the drugs during the Sunday barbecue. There was even some talk among the investigators that the killings may have been gang-related, prompting them to bring in a gang unit from Spokane to go over and study the crime scene. But after all was said and done, there was no indication that the crime was gang-related.

So who killed Brenda and Slade Groene, and Mark McKenzie, and kidnapped Shasta and Dylan Groene? And why? Were the children even still alive? At this point it appeared that there would be no easy answers to those questions and many others, and it seemed that any semblance of answers would not be forthcoming anytime soon.


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