Joseph Duncan
Also known as: Joseph Edward Duncan III
- Active
- 1996–2005
- Region
- Coeur d'Alene, Idaho, USA
- Kind
- Serial
- Status
- Convicted
- Victims
- 7
Joseph Edward Duncan III, a convicted sex offender who had served prison time for raping a boy in 1980, killed Brenda Groene, her fiancé Mark McKenzie and her 13-year-old son Slade at their home near Coeur d'Alene, Idaho, in May 2005, and abducted two of her younger children. He took them to a remote campsite in western Montana, where he killed 9-year-old Dylan Groene. On July 2, 2005, staff and customers at a Coeur d'Alene Denny's recognized Dylan's 8-year-old sister, Shasta, and Duncan was arrested there. He pleaded guilty to the Idaho murders, was sentenced to death in federal court in 2008 for Dylan's kidnapping and murder, and later pleaded guilty to the 1997 murder of Anthony Martinez in California. He also confessed to killing two Seattle girls in 1996. He died on federal death row in 2021.
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Victims
We remember the people whose lives were taken.
- Brenda Groene, 40 · May 2005
- Mark McKenzie, 37 · May 2005
Brenda Groene's fiancé.
- Slade Groene, 13 · May 2005
- Dylan Groene, 9 · 2005
- Anthony Martinez, 10 · 1997
- Sammie Jo White, 11 · July 1996
Duncan confessed to killing her and her half-sister; he was never charged.
- Carmen Cubias, 9 · July 1996
Duncan confessed to killing her and her half-sister; he was never charged.
Timeline of locations
- July 6, 1996Seattle (Abduction, approximate area)
Half-sisters Sammie Jo White and Carmen Cubias disappeared after leaving a Seattle motel on July 6, 1996.
- 1997Beaumont, California (Abduction, approximate area)
Ten-year-old Anthony Martinez was abducted in Beaumont, Riverside County, in 1997 and killed.
- February 10, 1998Bothell, Washington (Recovery site, approximate area)
The girls' remains were found in Bothell on February 10, 1998.
- May 2005Groene home, Coeur d'Alene area (Crime scene, approximate area)
Duncan killed Brenda Groene, Mark McKenzie and Slade Groene at the family's home in Kootenai County and took Dylan and his younger sister.
- July 2005Lolo National Forest, western Montana (Recovery site, approximate area)
Duncan held the children at a remote campsite in western Montana, where he killed Dylan. His remains were found in the Lolo National Forest in July 2005. The marker is regional only.
- July 2, 2005Denny's restaurant, Coeur d'Alene (Arrest, approximate area)
On July 2, 2005, a waitress and customers at a Coeur d'Alene Denny's recognized the missing girl with Duncan and called police, who arrested him there.
- 2008USP Terre Haute, Indiana (Prison, approximate area)
Duncan was held on federal death row at Terre Haute and died of brain cancer at a nearby hospital on March 28, 2021.
- August 27, 2008U.S. District Court, Boise (Court / trial, approximate area)
Representing himself, Duncan was sentenced to death by a federal jury on August 27, 2008, for Dylan's kidnapping and murder; Judge Edward Lodge imposed life terms on the remaining counts that November.
Active at the same time, nearby
- Gary Ridgway · both active in 1996, 16 km apart · map both
- Robert Lee Yates Jr. · both active in 1998, 72 km apart · map both
- Lonnie Franklin Jr. · both active in 1997, 123 km apart · map both
A coincidence of time and place, not a connection. All overlaps
Sources
- Joseph E. Duncan III (Wikipedia)
- Idaho child killer is sentenced to death (NBC News / AP, August 2008)
- 'My soul is lighter': Northwest serial killer dies of brain cancer, bringing closure to families (Fox 13 Seattle / AP)
- Judge upholds 2 death sentences for Joseph Edward Duncan III (KSL / AP)
Each location also lists its own sources in the data file.