The 21st century has seen a massive increase in how neuroscience is used to influence the legal system, from evidence to policy decisions.
Nita Farahany, a bioethicist at Duke University has been tracking the rise of legal cases involving neuroscience evidence in the U.S. The number of judicial opinions mentioning neuroscience evidence tripled between 2005 and 2011, from roughly 100 to more than 300. “It’s more prevalent than my numbers show,” Farahany said. That’s because most cases involving neuroscience evidence do not result in a written judicial opinion, and those that don’t are exceedingly difficult to find.
Common uses of neuroscience evidence, Farahany has found, include establishing whether a defendant is competent to stand trial, and mitigation during sentencing, along the lines of the evidence presented in McCluskey’s trial. Another common use, and perhaps an even more telling one, is to establish ineffective assistance of counsel (in other words, to establish that an attorney isn’t doing a good enough job for a client). For example, Farahany says, a defendant might try to convince a judge to order a new trail or dismiss a case altogether because his attorney failed to investigate a neuroscience-based claim regarding his mental state.
There was a modest dip in the number of cases involving neuroscience in 2012, which Farahany attributes to fewer capital cases overall that year. Capital cases, ones in which the death penalty is on the table, make up a large proportion of the cases in her analysis. She’s just starting to look at the data for 2013, but so far she says it appears the numbers will be at least as high as those for 2012. She presented her findings at a recent meeting and will describe them in more detail in a paper in press atNature.
Evidence presented in individual cases is just one way in which neuroscience is influencing the legal system. Brain science is playing a role in legal and policy decisions in other ways too. Sometimes that’s a good thing. But it comes with the risk of getting too far out ahead of the science and basing real-world decisions on research that’s too preliminary or otherwise unready for prime time. Below we’ve rounded up several recent developments that illustrate what’s happening — for better and worse — and hint at what the future may hold.