Using genetic evidence as a defense in criminal testimony is becoming more common. However, new research shows that pleading on behalf of your genes doesn’t make you appear any less responsible to the judge and jury.
A defense strategy may employ behavioral genetic evidence that links gene variants or gene DNA to establish a root cause for a crime or any violent tendencies/behaviors that may have motivated a crime.
Research has found links to genetic makeup and criminal behavior, but these relationships are still largely unexplored. This is why the use of behavioral genetics in court in most cases doesn’t aid the defendant.
A new report by Dr. Paula Appelbaum from Columbia University Medical Center and Nicholas Scurich from the University of California, Irvine, published in the journal Nature Human Behaviour, discusses why juries are likely to be unsympathetic to arguments founded around genetics.
The authors noted that even if a jury is sympathetic to behavioral traits, there still won’t be a ruling in the defendant’s favor because of the possibility of future offenses.
“A judge and jury may find defendants are less responsible because of a genetic factor, but also feel that they are more likely to re-offend because they can’t control themselves due to the genetic effect,” said Appelbaum.
According to the law, inherited traits are not enough to deter blame for one’s actions. In order to plead insanity, for example, or exhibit reduced behavioral control, there has to sufficient proof that the defendant was not in control of their actions.
In order for genetic data to continue to be used as a defense in the criminal courts, more studies will need to be conducted to show plausible links between criminal behavior and genes.
“Until that evidence is forthcoming, the use of behavioral genetic data in the criminal justice system is likely to diminish. For the time being, at least, not relying on genetic evidence in criminal courts may result in fairer outcomes at every level,” said Applebaum.