Neuroscience in Law; Using Developmental Studies to Determine the Maximum Juvenile Age

 After hearing Dr. Katrina Sifferd discuss the applications and implications of neuroscience in legal processes, I became very interested in finding out more about this topic especially as it pertained to developmental neuroscience. Although science has always been a significant part of the legal process from forensics and evidence interpretation to expert testimonies, many of the applications of neuroscience to law are just beginning to emerge. This leaves professionals with a duty to determine the ethical and practical limits and the appropriate applications of neuroscience without precedence. While investigating this subject, I came across an article by Dr. Stephan Schleim titled “Real Neurolaw in the Netherlands: The Role of the Developing Brain in the New Adolescent Criminal Law” that focused significantly on the interactions between neurolaw and neuroethics. I found this same intersection fascinating in Dr. Sifferd’s speech and was excited to see the opinion of another expert. I also began to wonder, what credentials or qualifications makes someone an expert? What is required for someone to publish a paper on neuroethics in a peer reviewed journal? Does someone need formal schooling to be considered an expert or would life and career experience be deemed sufficient for a publication? 

While many papers discussed when neuroscience evidence and analysis could be used in a courtroom, this article uniquely touched on a less theoretical, futuristic different topic. In this article, Dr. Schleim explores the existing laws and legal justifications used to determine the age at which juvenile criminal laws cease to be applicable in the Netherlands. Determining the age at which someone is, legally, treated like an adult is a very interesting topic. The severity and type of consequences given to an adult and a child can vary significantly. But how does a legal system decide who should be tried as an adult and who should be tried as a child? Is it based on simply age? Emotional maturity or awareness of the consequences of their actions? Should this vary with severity of crime? How can this be standardized? Or should it not be standardized and, rather, decided on a case by case basis? If it is done on a case by case basis, how can a fair process be ensured? What level of evidence would be needed for a process to be standardized across various countries or legal systems? 

As reported in this article, in the Netherlands, neuroscience findings were used to justify raising the maximum age for which juvenile criminal law could be applied to 22. However, the same law that raised the applicable age of juvenile law also increased the maximum juvenile sentence and made it possible that juveniles could receive an indefinite sentence length. This law is a concrete example of how neuroscience has already begun to influence legal proceedings and decision making. Lawmakers considered the neuroscience of responsibility, behavior, cognition, and emotion. Should lawmakers have a neuroscience background to analyze and apply research on these topics legally? Is advising from experts in the field sufficient? Again, what qualifies someone as an expert? 

When Dutch lawmakers were creating this law, the State Secretary commented on the lack of development of brain functions necessary for “socially desired behavior” for individuals under the age of 20. The Secretary of State also claimed that lawmakers took into consideration impulse inhibition, emotional regulation, and long-term consequences/planning capabilities when determining what ages could be legally considered juvenile. The State Secretary indicated that these stances were based on relevant research studies. They stated that it is believed these developmental aspects influenced the behaviors of adolescents and lead to more criminal behavior in adolescents. When publicizing a law to increase the legal juvenile age, the State Secretary further emphasized that scientific findings and research were used to inform their decision making process. He emphasized the neurobiological findings that individuals from age 15 to 23 are more likely to engage in risky behaviors that can be attributed to their brain still developing important functions. Although many countries consider an 18 year old to be an adult because of the social and life changes that occur for many 18 year-olds, science has shown that an 18 year old does not have a fully developed brain. An 18 year old is still forming important emotional, social, ethical, and knowledge foundations. The prefrontal cortex functions continue developing until the age of 25. However, most criminal behavior attributed to ongoing development ends by the age 23. I am curious how we will ever know if someone is fully done developing? Do we base this on the scientific average of 25 years old or should someone's juvenile status be based on their individual level of neural development? Can this be known without previous brain imaging? Does this vary for individuals with developmental delays? Should individuals with certain developmental delays be considered juveniles by the law for longer? Does someone have to have full brain development  (around age 25) to be held fully responsible for their actions and receive the adult consequences? Or is there a percentage of development (occurring around age 23) at which someone is expected to have enough emotional development and awareness of long-term consequences to be held responsible with the adult legal system? If there is a percentage or level of development at which this is reasonable, what can scientifically indicate that percentage or level on an individual basis? Can an individual’s level of development be used therapeutically to improve behavior and avoid future criminal acts? What happens at age 23 that makes an individual less likely to commit a crime despite the fact that their prefrontal cortex still has to undergo two more years of development? The neuroscience and psychology used to justify this Dutch law also discussed the adolescent’s susceptibility to peer pressure and lack of autonomy. Dutch lawmakers expressed that adolescents do not fully develop until the age of 23. Why then is the maximum applied juvenile age in the Netherlands 22 and not 23? Would someone who is a few days short of turning 23 truly have a different amount of cognitive development than someone who turned 23 a week prior to committing a crime? What about the development that occurs between the ages of 23 and 25? Is this not as relevant to legal decision making?

In Dr. Schleim’s analysis of the studies used to justify this legal change, he points out that, while the law creates options to treat 12 and 22 year olds similarly (legally), fMRI data from one of the cited studies, Adleman and colleagues (2002), indicates that there are brain matter differences between these age groups. Additionally, this study did not include anyone over the age of 22 so there are not any participants who would be definitely considered legal adults with which data could be compared. Finally, this study also found that there were no differences between adolescents and children. This contradicts the legal standing that children and adolescents are separate categories and are treated differently. The second cited study, Casey and colleagues (2005), actually claims that the brain is almost done developing by the age of 16. This further contradicts the neurobiological justification provided by lawmakers when introducing this new law. Finally, the third cited paper, Paus and colleagues (2001) states that neural development continues until the age of 30. However, the rate of development does slow with age. If these findings do not fully and explicitly support the legal change that occurred in the Netherlands, is this application of these studies ethical? Should further research have been done before a legal change was made? What would be considered sufficient research?