Insanity Evaluations in the Age of Neuroimaging

The insanity defense has a lengthy and complicated history in law. Retrospectively evaluating an individual’s mental state is a complicated endeavor as forensic examiners seek to understand the relationship between behavior and mental states. The reliability on insanity defense opinions in forensic reports is lower than other types of forensic evaluations and it has been suggested that using neuroimaging in these evaluations could improve their reliability. Relying on actual cases and scientific evidence, this chapter reviews how neuroimaging has been used and misused in insanity evaluations. By considering how neuroimaging has been employed in insanity cases, the reader can get a more in-depth understanding of some of the strengths and weaknesses of this technology and how it is utilized in court. Overall, the use of neuroimaging may not be as helpful as some claim due to significant limitations with retrospectively determining the state of an individual’s brain and their motivations.