Joseph Duncan
Summary
Joseph Edward Duncan III is the murderer and kidnapper who attacked a Wolf Lodge Bay family in May 2005.
Kootenai County deputies discovered three dead on May 16, 2005. Brenda Groene, 40; her fiance Mark McKenzie, 37; and her son, Slade Groene, 13, were bludgeoned to death. An Amber Alert was issued the next day for Brenda Groene’s two youngest children, 9-year-old Dylan Groene and 8-year-old Shasta Groene.
The murders and children’s disappearance launched the biggest investigative effort in Kootenai County’s history, at one point involving more than 100 FBI personnel and more than 80 investigators from several other agencies.
Shortly before 2 a.m. on July 2, Shasta was recognized by workers and patrons at the Denny’s in Coeur d’Alene, and her kidnapper, Duncan, was arrested without incident.
Duncan, 42 at the time, was a federal fugitive and a Tacoma native who had spent much of his adult life in Washington state prisons for sex crimes against children. He was on the run from a child molestation charge in Minnesota when he drove past the Groene home on Interstate 90 east of Coeur d’Alene and spotted Shasta and Dylan playing outside.
Over the July 4 weekend, investigators found Dylan Groene’s remains at a campsite near St. Regis, Mont.
On Oct. 16, 2005, Duncan pleaded guilty to three counts of kidnapping and three counts of murder in the deaths of Brenda Groene, Mark McKenzie and Slade Groene. He was sentenced to three consecutive life sentences for the kidnappings. The sentences for the murders were undecided, pending federal prosecution.
More than two years later, after numerous legal delays and psychiatric evaluations, Duncan acted as his own lawyer as he pleaded guilty to 10 federal counts, including the kidnapping of the two children and Dylan’s murder, on Dec. 3, 2007.
On Aug. 27, 2008, a federal jury sentenced Duncan to death. The decision ended the state’s earlier case, with a judge imposing three more life sentences for those murders. Later, Duncan was given three more life sentences, for a total of nine, for his federal crimes.
Duncan pleaded guilty in the death of Anthony Martinez, a 10-year-old California boy, adding his 10th life sentence on March 15, 2011. Duncan has also been linked to the 1996 slayings of two young half-sisters in Seattle.
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Bill Douglas / Duncan sentencing
August 28, 2008 in City, Idaho Kootenai County prosecutor reacts to Joseph Duncan’s death sentence on “On the Record with Rebecca Mack.”
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Amber Deahn / Duncan sentence
August 28, 2008 in City, Idaho Amber Deahn, the waitress at Denny’s who spotted Joseph Duncan with Shasta Groene, reacts to Joseph Duncan’s death sentence on “On the Record with Rebecca Mack.”
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Betsy Z. Russell / after Duncan sentencing verdict
August 28, 2008 in City, Idaho Boise reporter Betsy Z. Russell follows up on Joseph Duncan’s death sentence on “On the Record with Rebecca Mack.”
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Darlene Torres / Duncan sentencing, part 2
August 27, 2008 in City, Idaho Darlene Torres, Dylan Groene’s grandmother, reacts to the death sentence given to Joseph Duncan.
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Darlene Torres / Duncan sentencing, part 1
August 27, 2008 in City, Idaho Darlene Torres, Dylan Groene’s grandmother, reacts to Joseph Duncan’s death sentence.
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Steve Groene / Duncan’s death sentence, part 2
August 27, 2008 in City, Idaho Steve Groene reacts to Joseph Duncan’s death sentence.
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Betsy Z. Russell / Duncan’s past crimes
August 25, 2008 in City, Idaho Boise reporter Betsy Z. Russell talks about testimony about Joseph Duncan’s past crimes during his death sentence trial on “On the Record with Rebecca Mack.”
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Betsy Z. Russell / Dunca sentencing trial 2nd phase
August 22, 2008 in City, Idaho Boise reporter Betsy Z. Russell talks about the second phase of the Joseph Duncan sentencing trial.
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Steve Smith / Covering Duncan trial
August 21, 2008 in City, Idaho Then-editor Steve Smith talks about the Spokesman-Review’s coverage of the Joseph Duncan sentencing trial.
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Betsy Z. Russell / Jurors view graphic Duncan videos
August 21, 2008 in City, Idaho Boise reporter Betsy Z. Russell talks about the showing of graphic videos filmed by Joseph Duncan during his sentencing trial on “On the Record with Rebecca Mack.”
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Betsy Z. Russell / Duncan’s GPS device
August 13, 2008 in City, Idaho Boise reporter Betsy Z. Russell talks about testimony regarding Joseph Duncan’s GPS device on “On the Record with Rebecca Mack.”
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Betsy Z. Russell / Duncan’s courtroom behavior
August 11, 2008 in City, Idaho Boise reporter Betsy Z. Russell talks about Joseph Duncan’s behavior in court during his sentencing trial on “On the Record with Rebecca Mack.”
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Betsy Z. Russell / Duncan’s graphic video
August 11, 2008 in City, Idaho Boise reporter Betsy Z. Russell talks about Joseph Duncan’s graphic video on “On the Record with Rebecca Mack.”

Spokane7
Joseph Duncan
Brenda Groene
Mark McKenzie
Steve Groene