Video project for NSC 316 at Smith College.
We’ve all given into our impulses. We go online shopping or watched that next TV show episode instead of doing work. Maybe you’re watching this video on an impulse now. In general, we rein in these impulses to keep ourselves functioning normally and productively. Impulse control disorders, or ICDs, occur when neurological or psychological issues compromise control of impulses like these. Regrettably, sometimes they can lead sufferers to criminal behavior. Understanding how the criminal justice system deals with these disorders sheds light on the complexities interaction between mental illness and the law.
In the general population, symptoms of ICDs have a 33% lifetime prevalence rate. Abnormalities in the brain’s prefrontal cortex are associated with impulse control issues. The list of recognized ICDs include Intermittent explosive disorder, which involves explosive bouts of anger, kleptomania (or urges to steal), and pyromania (fire-setting). General impulse control dysfunction can also accompanies ailments like schizophrenia, or traumatic brain injuries. When ICDs lead to criminal behavior, the concept of criminal responsibility allows mental illness to be an extenuating circumstance.
Criminal Responsibility is the legal judgement that someone who committed a crime bears responsibility for it. Without this, suspects are usually not held to be guilty of the crime, even if they performed the criminal action. Different states have different standards for mental illness. 22 states use the 1962 American Law Institute standard, which finds that someone who lacks criminal responsibility is… “by reason of mental disease or defect … either unable to appreciate the wrongfulness of their behavior or unable to conform their behavior to the requirements of the law.” For the other 24 states with insanity defenses, the M’Naughten rule applies. There, individuals are off the hook if they do not “know the nature… of the act” they did, ignoring any issues of control. Finally, 4 states allow no insanity defense.
Courts task forensic psychologists with determining the defendant’s mental state during the crime. They then report their findings to the court, but this evaluation can only go so far. In the end, the judge and jury decide if the defendant meets the criteria for lacking criminal responsibility. Overall, only a quarter of not guilty by reason of insanity pleas are successful. In the state of Maryland, only 11% of NGRI pleas are based on claims of lack of control, far outweighed by pleas based on lack of knowledge of right or wrong. Most often encountered, People with ADHD, manic phases, or past brain trauma are evaluated for criminal responsibility. Crimes caused just by ICDs are rare.
Expanding neuroimaging use can add new dimensions to forensic evaluation. It can shed light on neurological sources of impulse control dysfunction in the brain. Still, understanding how observed brain deficits affects behavior can be difficult. Knowing whether what you see actually affect the mind is difficult to answer. Some individuals can have brain abnormalities with no apparent ill effect. Nonetheless, neuroimaging offers promise in cut and dry instances of clear neurological damage. But remember, isolated impulse control disorders aren’t usually encountered by the criminal justice system.
Because the control-related behavior more commonly stems from manic phases, or ADHD-sparked impulsivity, it’s not as easy to verify the extent of dysfunction. We must also realize that however much technology we develop, we can never know the defendant’s true mental state at the time of the crime. Finding out if a defendant was truly unable to control their impulses, or simply chose to give in to them is most certainly beyond our current technological capabilities. Forensic psychologists have to do their best to find this out, and it’s not always easy. In the end, given the state of the field, it’s inevitable that for now, impulse control dysfunction causing criminal behavior will be a tough sell to explain in court.