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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Judge: Courtroom stays open for Duncan hearing
January 17, 2013 in City, Idaho, Region BOISE — A federal judge has rejected a request that the courtroom be closed for part of a convicted murderer’s mental competency hearing. 2
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Duncan’s defense attorneys request closed court
January 14, 2013 in City, Idaho BOISE — The former attorneys for convicted murderer Joseph Duncan are asking a judge to let them testify in secret about whether Duncan was mentally competent during his death penalty … 5
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Doctor claims Duncan’s competent
January 10, 2013 in City, Idaho on Page A6 BOISE – A forensic psychologist who examined convicted murderer Joseph Duncan four years ago said Duncan scored high on a test measuring paranoia, but was still legally competent to serve … 5
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Duncan had eye on Spokane child
January 9, 2013 in Idaho on Page A1 BOISE – Before Joseph Duncan murdered a 9-year-old North Idaho boy in 2005, he set his sights on a Spokane child, posing as a prospective renter and touring a South … 2
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Duncan targeted Spokane child
January 8, 2013 in Idaho Before Joseph Duncan murdered a 9-year-old North Idaho boy in 2005, he set his sights on a Spokane child, posing as a prospective renter and touring a Spokane duplex with … 8
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Killer Joseph Duncan gets new hearing
January 8, 2013 in Idaho on Page A5 BOISE – Joseph Duncan was sentenced to death three times over for crimes against a 9-year-old North Idaho boy he killed in 2005, and he initially and repeatedly said he … 18
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Killer’s competency appeal nears in federal court
December 17, 2012 in City, Idaho As an appeal over the competency of a convicted child killer nears in Idaho’s U.S. District Court, a judge is sorting out just what expert witnesses should be allowed to … 5
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Groene kids’ dad sues donation fund manager
June 14, 2012 in Idaho COEUR D’ALENE — A woman who administered a bank account for donations given to benefit two North Idaho children kidnapped seven years ago is being sued by their father, who … 1
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Duncan’s competency hearing set
June 5, 2012 in Idaho on Page A6 BOISE – A court hearing on whether condemned murderer Joseph Duncan was mentally competent when he waived his right to appeal his death sentence has been set for Jan. 8, … 1
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Duncan competency hearing set for January
June 4, 2012 in Idaho A court hearing on whether condemned murderer Joseph Duncan was mentally competent when he waived his right to appeal his death sentence has been set for Jan. 8, 2013.
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Duncan alters course on sentence appeal
May 19, 2012 in Idaho on Page A1 BOISE – Notorious murderer Joseph Duncan has changed his mind about waiving his right to appeal, saying he owes it to his mother to try getting off death row for … 14
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Duncan’s competence at sentencing to be reconsidered
March 29, 2012 in City, Idaho on Page A1 Condemned serial killer Joseph E. Duncan is getting another day in court. Duncan, on death row for the torture and slaying of a North Idaho boy he abducted in 2005 … 2
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Duncan sentence faces test
July 12, 2011 in Idaho on Page A5 BOISE – The 9th U.S. Circuit Court of Appeals has ordered convicted killer Joseph Duncan back into court in Idaho, saying a federal judge should have ordered a competency hearing … 1
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9th Circuit orders Duncan back into court in Idaho
July 11, 2011 in Idaho, News The 9th Circuit U.S. Court of Appeals has ordered convicted child-killer Joseph Duncan back into court in Idaho, saying a federal judge should have ordered a competency hearing before allowing … 19
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Huckleberries: Strangers reward woman’s effort to turn life around
April 10, 2011 in City on Page B3 Kendra Martinez has kept herself out of trouble since the days of yore when she was the object of a tug-of-war between the Kootenai County prosecutor and the public defender. …
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Joseph Duncan given two more life sentences
April 5, 2011 in City, News Convicted serial killer Joseph Duncan received two more life sentences today for the 1997 murder of Anthony Martinez in southern California. 7
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Joseph Duncan guilty plea brings 10th life sentence
March 15, 2011 in City, Idaho A convicted mass-murderer pleaded guilty today to the 1997 murder and torture of 10-year-old Anthony Martinez in exchange for life in prison without parole. 10
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Duncan lawyers offer to settle California case
February 23, 2011 in City on Page A6 Defense attorneys for the man accused of killing a 10-year-old Beaumont, Calif., boy in 1997 have offered to settle the case with prosecutors. During a hearing Tuesday morning in an …
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Duncan may offer plea deal in California case
February 22, 2011 in News, Region Defense attorneys for the man accused of killing a 10-year-old Beaumont boy in 1997 have offered to settle the case with prosecutors. 10
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Duncan requests attorney ahead of California trial
October 5, 2010 in City on Page A6 Convicted killer Joseph Edward Duncan, already condemned to die for a murderous North Idaho rampage in 2005 and about to stand trial in California for an earlier slaying, has reconsidered …

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Joseph Duncan
Brenda Groene
Mark McKenzie
Steve Groene