Neuroscience and neuroimaging are unequivocally useful for determining an individual’s fitness to stand trial. They also aid our understanding of areas of the brain responsible for a person’s behavior and decision making processes. Other applications of neuroscience in law such as lie detection tests and go/no-go tests are currently either: bias, less reliable, less replicable, or all the above.
Neuroimaging is the current frontier of neuroscience and specifically informs two baselines: (1) the locations of neuronal activity, and (2) the activity levels within those regions (Li et al., 2012). By holding the stimulus and environment constant across large enough sample populations, it becomes possible to identify common brain areas associated with completing a task and expected brain activity levels within those regions.
For example, reactive aggression[1] is particularly common amongst domestic abusers. By using neuroimaging, it is possible to observe brain activity associated with this type of behavior (Figure 1). MRI readings show greater activity in the amygdala and reduced activity in the anterior cingulate cortex (ACC). [2] This implies that neuroimaging could help identify the best approaches for rehabilitating convicted criminals. In this example, an individual in the experimental group may benefit from a therapy involving self-regulation and impulse control, such as Cognitive Behavioral Therapy (CBT) (Smeets et al., 2015).
In a different sample population [of non-criminals] with varying degrees of psychopathic personalities, it is possible to observe a near-opposite trend in brain activity (Figure 2). Neuroimaging shows a reduced amygdala response, as well as reduced prefrontal activity (Glenn et al., 2009).[3]
However, these technologies do not deliver vital considerations in a person’s culpability: the direct motives and thoughts that guided their actions. Modern neuroscience and technology are not yet equipped to be a primary source of evidence in criminal convictions. Thus, as it relates to informing decisions about a unique criminal and his behavior, neuroscience should be used as a means of deciding whether he is fit to stand trial and the most effective way to rehabilitate him for reintegration into society.
The best application would be to initially focus resources on existing offenders, and later target preventative care to individuals with a predisposition for crime. To this end, my suggestion for future research would involve improving our understanding of the role of neuroscience in the treatment of mental disorders. This is because when we discuss the incarcerated, it must not be understated how deeply mental illness affects the criminal population. A considerable portion of these individuals are sufferers of at least one major personality disorder (Simpson et al., 1999), and many criminals/former convicts have an increased likeliness to reoffend because of systemic failures to support, treat, and rehabilitate them, and/or because their incarceration exacerbates their dysfunction.
When a criminal chooses to undergo trainings or therapies as a part of her incarceration rehabilitation program, offering a baseline neuroimaging scan (pre-incarceration) and comparing it to ongoing or post-incarceration scans may show cognitive development due to the patient’s own neuroplasticity and adaptive learning capabilities. This would likely appear in neuroimaging either via different [from baseline] levels of brain activity in some regions, or visibly altered activations of neural pathways (Khan et al., 2017).
On the basis that such comparisons were proven scientifically sound, and if the inmate were able to consistently demonstrate normal neural responses to a classifiably identical stimulus, neuroimaging could indicate an effective therapy process, and likely assist her if she sought special privileges or early release. Similarly, if neuroimaging were carried out throughout the rehabilitation process, it may be possible to detect ineffective methods of treatment early-on to minimize an inmate’s propensity for recidivism.
Neuroimaging can identify areas of the brain which are either underactive or overactive in response to different stimuli and use this information to predict an individual’s predisposition for certain types of crime, but these technologies do not inform an individual’s direct thoughts or motives, nor do they guarantee criminal behavior and so should not be used as grounds for conviction.
When using a more experimental neuroscientific approach it also becomes difficult to extrapolate meaningful insights. The go/no-go test is one such example: it is a simplified measurement of impulse control by experimental design (Aharoni et al., 2013). However, using an individual’s ACC activity as an indicator of rearrest is different to using this type of information to make inferences about groups of people. Additionally, there is some disagreement in the scientific community about the exact role of the ACC. Therefore, this is not particularly helpful on a case-by-case basis due to natural human variability and scientific dissent. In brief, there is certainly great potential for future synergies between neuroscience and law, but neuroimaging and assessments of fitness to plead are the strongest current applications. At present, there is much more potential for neuroscience in criminal rehabilitation than detecting criminals in the population or predicting a released person’s likelihood for re-arrest. Focusing on convict rehabilitation also emphasizes the need for reintegration over punitive justice and prioritizes the needs of citizens.
Footnotes
[1] Reactive aggression is a response to an anger trigger, while instrumental aggression is when a goal-directed individual uses aggression as a tool for manipulating others. These two types of aggression are distinct from one another and typically found in different types of individuals. Reactive aggression is prevalent in many psychological disorders, while instrumental aggression is classically a psychopathic tendency.
[2] The amygdala is responsible for emotional reactivity. In a trial of spouse abusers reacting to negative words, the experimental group had overreactive amygdala in the presence of the stimulus and underactivity in the ACC; a part of the brain which contributes to rationalization and emotional/behavioral regulation (Lee et al., 2008).
[3] The prefrontal cortex is the regulation system involved in interpreting and responding to a stimulus. Individuals with psychopathic traits showed less activity in neuroimages of this brain system when faced with emotional moral decision making (Glenn et al., 2009).