Study Details the Effect of Brain Scan Evidence on Sentencing
by Anthony Accurso
A new study shows that neurobiological evidence (brain scans) used at sentencing may reduce the amount of prison time prescribed at sentencing but may conversely also increase the amount of prescribed involuntary hospitalization.
This study performed by researchers at Georgia State University used controlled surveys of volunteers to determine the impact of evidence of an impulse control disorder on sentencing.
The evidence for this disorder was either presented as having a neurobiological cause (as shown by an abnormal brain scan) or merely a psychological one. The condition also was variously presented as treatable or untreatable. Participants were given the option to allocate some of the sentence between prison time and involuntary hospitalization.
Compared to the baseline (in which the hypothetical offender has no diagnosed impulse control disorder), participants were likely to reduce the amount of prison time by 33 percent when presented evidence of a psychological disorder that was untreatable and by 54 percent when it was treatable. When presented with neurobiological evidence, prison times were reduced even further, with the treatable case resulting in a 74 percent reduction in prescribed prison time compared to the untreatable case, which resulted in a 53 percent reduction.
However, the diagnosis was likely to elicit longer prescribed periods of involuntary hospitalization when compared to the baseline. Neurobiological evidence resulted in longer prescribed terms of involuntary hospitalization than mere psychological evidence, and the terms were longer for untreatable conditions in both cases. An untreatable condition shown to have a neurobiological basis resulted in a 155 percent addition of hospitalization time compared to the baseline prison time.
In short, providing neurobiological evidence of a treatable impulse-control disorder resulted in the lowest amount of prescribed prison time, while neurobiological evidence of an untreatable disorder resulted in the longest time prescribed for involuntary hospitalization.
One caveat to this research is that while the researchers note that brain-scan evidence is being used for leniency in 5 percent of murder cases at the appellate level and 25 percent of death penalty trials, the hypothetical offense upon which participants made their judgments was sexual assault, not murder.