Will your genetic defense for that violent crime backfire?
The growing body of research on genetic variations and their relation to crime may leave you uncertain about how to best defend your client charged with a violent crime. Do you encourage jurors to support an insanity defense by using a genetic defense or does that route backfire and leave jurors seeing your client as “different, dangerous, and likely to reoffend”? New research says it isn’t all straightforward and jurors may hear your defense in a way that biases them against your client.
Researchers in Canada conducted three experiments with a total of more than 600 participants to examine the effect a genetic defense for a violent crime might have on the listener. The researchers offered variations on a nature versus nurture defense in a (fictional) murder committed by a college student.
Specifically, one group read that the defendant had a genetic variation associated with aggression and violent tendencies (i.e., MAOA which is also nicknamed “the warrior gene”).
The second group read that the defendant had been beaten as a child by his single mother and grew up in a neighborhood populated with gangs. Both of the first two groups were told that either a genetic (i.e., nature) or environmental (i.e., nurture) background could result in a four-fold increase in the likelihood of violent behavior.
The third group (a control group) read about the murder but did not receive any information on the defendant.
The researchers spend some time explaining the concept of mens rea:
“a legal concept pertaining to one’s malicious intent and volition to commit a crime” is necessary for a conviction. Perceiving someone’s actions as being beyond their control likely leads to the perception that the perpetrator lacked mens rea”.
Here is what they found across three studies (with both online recruits and university students as participants):
The group of participants who saw the genetic explanations for the murder were more likely to see the Insanity defense and Diminished Capacity defenses as legitimate than were those in the environmental explanation condition.
Those who were in the genetic condition also saw the perpetrator as less in control over his actions and less likely to be truly intending to harm the victim—but the genetic explanation did not change their sense the perpetrator knew the potential outcome of his actions.
Overall, say the researchers, the participants believed that the genetic explanations “diminished the defendant’s agency”. In other words, they explain, “despite knowing that his actions could have killed the victim, he neither was able to control his behavior nor did he really intend to kill the victim”.
Only participants in the third study thought the genetic defense decreased criminal responsibility. However, the length of the sentences assigned did vary somewhat. Those who had genetic explanations rather than environmental explanations thought the defendant had less conscious behavioral control. At the same time though, genetic defenses resulted in more sense the defendant would reoffend than did environmental defenses and that predicted lengthier sentences (since the defendant would be dangerous).
The researchers see this as the double-edged sword of the genetic defense: Jurors may see your client as less criminally responsible but they are more concerned about recidivism and dangerousness so they will want to lock your client up for a longer time. This is complicated by whether the jurors feel that he is NGRI (not guilty by reason of insanity) or GBI (guilty but insane). A NGRI verdict ends the trial, foregoing a punishment phase, while the latter can result in sentencing.
From a litigation advocacy perspective, this dilemma reminds us of our writings on the psychopath. Telling jurors that your client is a psychopath can be very convincing as a “his brain made him do it” sort of defense. The problem is that people are (fairly enough) very frightened by violent psychopaths, and have the belief that they are not subject to rehabilitation. Punishment is necessarily lengthened as jurors want to remain safe rather than having “that animal” back out on the streets.
It’s a good reason to carefully think through the pros and cons of any defense that leads the listener to see your client as irrevocably damaged. In some cases, your task is to make your client appear to be potentially rehabilitatable so that jurors don’t throw in a lengthy sentence to keep themselves “safe”. In other cases, it is enough to try to achieve a verdict that reflects psychiatrically impairment, instead of a guilty result. If the cause of the ‘insanity’ is a treatable condition, it is a much safer strategy to pursue from a punishment standpoint, but it is also harder to convince a jury of the non-volitional cause.
Cheung BY, & Heine SJ (2015). The Double-Edged Sword of Genetic Accounts of Criminality: Causal Attributions From Genetic Ascriptions Affect Legal Decision Making. Personality & Social Psychology Bulletin PMID: 26498975