The Return of Lombroso? Ethical Aspects of (Visions of) Preventive Forensic Screening

Munthe, Christian; Radovic, Susanna

The discovery of the so-called 'warrior gene' (Brunner et al., 1993) received great interest in the scientific community, suggesting that carriers of a low-activity variant of the monoamine oxidase A gene are more likely to display antisocial aggressive behaviour, an effect proven to depend on adverse childhood environment (Buades-Rotger et al., 2014) . Research has continued to look for specific genes associated with criminal behaviour, but despite the unanimous evidence that genetic effects are involved (adoption and twin studies have shown that hereditary factors explain about 65% of the difference in risk for aggressive antisocial behaviour (Burt, 2009) ), it has proved exceedingly difficult to pin precise behaviour patterns on specific molecular genetic variants (Lee et al., 2013; Vassos et al., 2014) . A typical problem, illustrated by a recent, highly publicized study (Tiihonen et al., 2014) , is that specific mutations found in offender populations may, first, be widespread also among non-offenders and, secondly, surrounded by an innumerable complex of confounding factors not controlled for. The evidence for a strong genetic explanation of the wider phenomenon of 'antisocial personality and behaviour' may at the moment look more compelling (Ferguson, 2010) . However, such explanations typically use diagnoses already conceptually assuming criminality or antisocial violence, making the suggested causal mechanism behind criminality (i.e. the conditions in question) imply circularity, and when sources of that are discounted for, the correlation between mental disorder and forensic risk tends to disappear , Nilsson et al., 2009 Even more uncertain is if the influence of specific genetic factors could ever be shown to be strong enough to ground the claims regarding detection and intervention (b and c above). The category of 'antisocial personality and behaviour' includes a wide variation of behaviour, a lot of which is not illegal. No evidence presently suggests that one single gene, or even a neat combination of a few ones, could be found that controls a certain behaviour, but rather that behaviour is influenced by a great number of genes working together in close interaction with complex environmental factors. This picture may come to change somewhat as biobankbased big data and large-scale epidemiological approaches to behavioural genomics are applied further (Nuffield Council of Bioethics, 2002; Simmons, 2008) , and psychiatric taxonomy is developed to allow multistep inferences from genetic explanations of conditions to causal explanations of relevant behaviour types. 6