Dr. Robert Engle testified Wednesday as part of a retrospective competency hearing ordered by the 9th U.S. Circuit Court of Appeals. The hearing is intended to determine whether Duncan was mentally competent when he waived his right to appeal his death sentence for the kidnapping and torture of two northern Idaho children and the murder of one of them.
Engle was appointed in 2008 by U.S. District Judge Edward Lodge to determine if Duncan's mental state should prevent him from representing himself in his federal death sentence hearing. At the time, Engle determined Duncan didn't have any mental defect or disease that would cause him to be legally incompetent.
Duncan snatched 9-year-old Dylan Groene and Dylan's younger sister from their Wolf Lodge, Idaho home after murdering several of their family members in 2005. He kept the children at a remote Montana campsite for weeks before he shot Dylan and returned with Dylan's sister to Coeur d'Alene, Idaho, where he was arrested.
Engle said he interviewed Duncan three times, administered several tests and asked Duncan about his past as part of his examination. The results showed Duncan was intelligent, that he didn't appear to be faking his test results, and that he wasn't delusional.
"He is not suffering from a mental defect or disease sufficient to impair his ability to choose to represent himself," Engle said on Wednesday.
Some of the test results were inconsistent with Engle's own observations of Duncan a fact Duncan's defense attorney Michael Burt focused on during his cross examination.
Duncan scored remarkably high on tests designed to measure whether he had symptoms of paranoia, schizophrenia and psychopathic deviancy, Engle said. The scores were so high, in fact, that Engle said he would have expected a person with those test results to be obviously delusional to anyone who encountered him.
"With a profile similar to Mr. Duncan's, many people are going to appear to behave psychotically," Engle told the court. "Their thinking may be described as autistic, circumstantial, tangential and bizarre ... they will show difficulties in concentrating, deficits in memory are common."
But Engle said he observed none of those symptoms when he interacted with Duncan, and he even had the company that originally scored the test recalculate the scores because he thought it might have been done incorrectly. When the identical results came back, Engle decided that he should put more weight on his own observations of Duncan than on the test results.
Duncan received a perfect score on one test that is specifically designed to measure a subject's legal competency, he said. It is possible for someone to have schizophrenia, paranoia or other mental illnesses and still be competent to represent themself in court, Engle said.
Duncan's defense attorney focused on the inconsistencies between some of the test results and Engle's observations, and tried to make a connection between some of the findings and events that Duncan talked about in his own life.
Burt alluded to Duncan's own confession to investigators that he was considering turning himself in for two murders he'd committed years earlier when he found a gun in a Missouri turkey shack and took it as a sign from God that he should go on a crime spree instead.
"So someone sees a gun, and they go and pick up the gun, and they say, 'I think this gun is a sign to me from God that I should go and do something.'" Burt said.
Would that amount to a type of paranoia symptom known as an "idea of reference," where an unrelated event or item is perceived as having special personal significance, Burt asked?
Yes, the psychologist responded.
Other symptoms measured by the tests, such as a person's difficulty relating to others or tendency to reject authority, could also have a negative impact on a defendant's relationship with their attorney, Engle acknowledged.
Duncan has been convicted of five different murders in Idaho, Montana and California. But the competency hearing focuses only on the crimes he committed against Dylan Groene and his sister.