Since it is election season in America, we can expect a new wave of social psychology papers claiming that political liberals are smarter and more creative than political conservatives. It makes good mainstream news fodder, just like sexism in hurricane names does. Some of the articles will even bolster their case with fMRI images to seem scientific.

Outside people with confirmation bias, surveys of college students done by psychologists are easily dismissed, but what about genetic data? A paper in Neuron argues that genetic evidence for criminality may be on the horizon. 

Some studies do suggest some people may be at greater genetic risk of criminal behavior but they are simplistic - find a lot of criminals and then find what genes they share in common. That's just waiting to be misinterpreted and misused.   

Genetic evidence is being offered in criminal trials to suggest that defendants have diminished understanding of or control over their behavior, most often in arguments for mitigating sentences—especially for defendants facing the death penalty. Genetic evidence may also play an increasing role in civil trials regarding issues such as causation of injury. For example, employers contesting work-related mental disability claims might want claimants to undergo genetic testing to prove that an underlying disorder was not responsible for their impairment.

 "Genetic evidence, properly used, could assist with judgments regarding appropriate criminal punishments, causes of injury or disability, and other questions before the courts," argues author Dr. Paul Appelbaum, who directs Columbia University's Center for Research on Ethical, Legal&Social Implications of Psychiatric, Neurologic & Behavioral Genetics. "The complexity of genetic information and our incomplete understanding of the roots of behavior raise the possibility that genetic evidence will be misused or misunderstood. Hence, care is needed in evaluating the extent to which genetic evidence may have something to add to legal proceedings in a given case."  

Moving forward, a number of questions must be addressed. For example, to what extent do specific genetic variants make it more difficult to understand or control one's behavior and what are the biological mechanisms involved? 

If criminality is genetic, is it also exculpatory?  What steps can society to take to make sure people with genetic predispositions have diminished risk of recidivism?

Appelbaum notes that it will be an ongoing challenge for both legal and genetic experts to monitor the use of genetic data in the courts to ensure that the conclusions that are drawn validly reflect the science. Without such efforts, judges and juries may overestimate or underestimate the conclusions that can be drawn from genetic evidence, thus unfairly distorting the legal process.