Has biology disproved free will and moral responsibility?

Abstract

In his Inaugural Article entitled “The Lucretian swerve: The biological basis of human behavior and the criminal justice system,” Andrew Cashmore suggests that penal systems based on moral responsibility have to be reformed because science has refuted the notion of free will (1). Brain imaging and other functional neuroscience methods have indeed been used not only to map neuronal covariates to behaviors but also to detect action potentials for simple movements hundreds of milliseconds before the conscious decision to act (2). Genetic factors have been shown to explain at least one half of the interindividual differences in the liability for criminality in different types of epidemiological study designs (e.g., adoption, twins, and family) (3), whereas molecular genetic studies indicate that no single genetic mechanism accounts for more than a couple of percentages of the variance in crime-related phenotypes (i.e., that the existence of one or a few “crime genes” can be discarded) (4). These facts are very useful. We now know that the chances to refrain from criminality are unfairly distributed and partly under the influence of constitutional susceptibility factors. Some of these, such as childhood hyperactivity and lead poisoning, have been identified in population-based epidemiological or clinical studies and may guide preventive efforts. Hopefully, this is just the beginning of a scientific endeavor to establish explanatory models and evidence-based, acceptable treatment for people at increased risk of aggressive antisocial behavior. Does it, however, have a bearing on moral responsibility and penal law?