Brain scan evidence in US courts examined through disputed research
8 reported1 unconfirmed
A Guardian investigation examines the use of brain scan evidence in US criminal courts, focusing on the work of researcher Kent Kiehl. Kiehl, a University of New Mexico researcher, has spent decades studying the brains of incarcerated people and has become a public face of criminal brain science. His research was first used in a 2009 death penalty case for serial killer Brian Dugan, where Kiehl testified that Dugan’s brain scans showed signs of psychopathy. The jury sentenced Dugan to death, though his sentence was later commuted to life in prison after Illinois imposed a death penalty moratorium. Since then, brain-based evidence has appeared in thousands of court cases, with defense attorneys using it to argue for lighter sentences. Critics argue the science is unreliable and echoes discredited eugenic thinking. The article notes that from 2005 to 2015, brain evidence appeared in more than 2,800 judicial opinions, with neurological arguments in about 10-12% of US murder trials and 25% of death-penalty trials.
What’s reported
Kent Kiehl is a researcher at the University of New Mexico who studies brains of incarcerated people.
In 2009, Kiehl testified in the death penalty trial of serial killer Brian Dugan, who had confessed to the rape and murder of a 10-year-old girl.
Kiehl used a psychopathy checklist and fMRI scans to assess Dugan, scoring him in the “highest range” of inmates he had met.
The jury sentenced Dugan to death; his sentence was later commuted to life in prison after Illinois imposed a death penalty moratorium.
From 2005 to 2015, brain evidence appeared in more than 2,800 judicial opinions, according to a 2019 study.
The study estimated neurological arguments for reduced criminal responsibility appeared in roughly 10-12% of US murder trials and about 25% of death-penalty trials.
Critics argue the science is unreliable and revives discredited eugenic thinking.
The article notes that people of color are disproportionately arrested, tried, and convicted at higher rates than white people in the US.
Open questions
The article does not specify the exact number of death sentences influenced by brain evidence or provide a definitive conclusion on the scientific validity of Kiehl’s methods.
Key figures
Kent Kiehl, researcher at the University of New Mexico
Brian Dugan, serial killer
Robert Hare, researcher at the University of British Columbia
Amos Joseph Wells III, defendant in a 2013 case
Sources: The Guardian
