Do polygenic indices capture "direct" effects on child externalizing behavior problems? Within-family analyses in two longitudinal birth cohorts

Aggression and Justice Involvement: Does Uric Acid Play a Role?

The search for biological markers that can be reliably linked to aggression and antisocial behavior has been central to the work of biological criminology. One such marker, uric acid, has long been suspected to play a causative role in promoting anger, irritability, aggression, and violence. Here, in this perspective article, we revisit some of the historical interest in uric acid as a compound relevant to brain and behavior, and reflect these early accounts off emergent scientific research. Advances in brain sciences, including neuropsychiatry and neuromicrobiology, have allowed for a more sophisticated understanding of potential mechanistic pathways linking uric acid with cognition and behavior. The updated science suggests that some of the early ideas surrounding uric acid and criminology had credibility. The available research strongly suggests that uric acid, as a potential biomarker of risk, is worthy of further research and close scrutiny. Informed by emergent gut-brain-microbiome research, we argue that certain aspects of early-to-mid-20th-century biological criminology were prematurely abandoned. From a legalome perspective, further advances surrounding uric acid and other gut-brain biomarkers can aid in shaping more humane, scientifically grounded policies that recognize the interplay between biology and environment.

The Legalome: Microbiology, Omics and Criminal Justice

Advances in neuromicrobiology and related omics technologies have reinforced the idea that unseen microbes play critical roles in human cognition and behaviour. Included in this research is evidence indicating that gut microbes, through direct and indirect pathways, can influence aggression, anger, irritability and antisocial behaviour. Moreover, gut microbes can manufacture chemicals that are known to compromise cognition. For example, recent court decisions in the United States and Europe acknowledge that gut microbes can produce high levels of ethanol, without consumption of alcohol by the defendants. The dismissal of driving while intoxicated charges in these cases-so-called auto-brewery syndrome-highlights the way in which microbiome knowledge will enhance the precision, objectivity and fairness of our legal systems. Here in this opinion essay, we introduce the concept of the 'legalome'-the application of microbiome and omics science to forensic psychiatry and criminal law. We argue that the rapid pace of microbial discoveries, including those that challenge ideas of free will and moral responsibility, will necessitate a reconsideration of traditional legal doctrines and justifications of retributive punishment. The implications extend beyond the courtroom, challenging us to reconsider how environmental factors-from diet to socioeconomic conditions-might shape preventative and rehabilitative efforts through their effects on the microbiome.