Law and Psychology: Jurors Face the Heart of Conflict

04/28/2015 05:58 pm ET | Updated Jun 27, 2015

Two high-profile, emotionally-charged criminal trials are currently underway in Colorado and Boston. The trial of James Holmes, the gunman who allegedly killed 12 and injured many others in the Aurora movie theater begins today. Also today, the lawyers for Dzhokhar Tsarnaev will begin their plea to the jury to spare his life.

These cases represent the intersection and overlap of two areas of expertise-- law and psychology, yet there are few clear answers to guide the jury. What makes this even more difficult is that these jurors are called to face a challenging conflict. In deciding whether these two men live or die, they have to to overcome the impulse for vengeance of innocent lives lost, while placing themselves inside the minds of their admitted killers.

In Boston, the defense team will weave together and offer for consideration, a narrative of the life of Mr.Tsarnaev. They will try to explain how a young man, considered by his friends and others to be "a normal kid" could become a terrorist and commit mass murder. This testimony will be offered not only to humanize him, but to diminish his culpability and avoid the death penalty by providing a psychological context for his crimes. Since he was only 19 at the time, they will argue that the environment he grew up in overwhelmed his capacity for clear thinking and good judgment and made him vulnerable to acts of violence and influence by his older brother.

This is where mental health, family dynamics and trauma psychology will be come into play. Lawyers will claim that a legacy of intergenerational trauma rooted in Chechen conflict over many years instilled a feeling of hopelessness, anger and despair in the Tsarnaev family. Dzhokhar's life was upended when his family fled their home and moved to the US when he was 8 years old. An environment of family instability and chaos created more emotional instability. His parents failed to assimilate, ultimately divorced and returned to Russia, and left him in the care of his older brother. Jurors will try to form a narrative and weave together a picture of the defendant's inner life and emotional development to decide if any of these traumas justifies some measure of leniency in the punishment phase of his trial.

In the case of James Holmes, the legal issue again hinges on mental health, but this trial raises the question of insanity at the time a crime was committed which means Colorado jurors have to determine whether Mr. Holmes was sane when he pulled the trigger. In Colorado, the prosecution carries the burden of proof to prove sanity. Again, jurors are being asked to confront difficult issues and profound conflicts related to state of mind and legal culpability, where innocent victims lives were taken in a heinous crime of violence. Ordinary citizens must squarely confront their own and society's widely held stereotypes and deeply held beliefs about insanity, gun violence, personal responsibility and mental health. Because we cannot take an x-ray or brain scan to determine one's state of mind, and there is no DSM diagnosis of "insanity" this question is far from straightforward. In fact, the methodical, premeditated planning of a crime, as in the Holmes case, can be evidence of a deranged mind as easily as it can be proof of controlled and conscious premeditation.

In these cases, we ask ordinary citizens to go beyond their assumptions and biases, manage their conflicting emotions and take on the difficult task of determining punishment for two heinous crimes that cry out for retribution. Our fellow citizens have an important task in front of them, for the sake of the victims and for our society as they tackle the difficult and sometimes awful truths of civilized life. For this task, we hope they have the right frame of mind.