Evolution and the law

A new paper by Brian Leiter and Michael Weisberg entitled “Why Evolutionary Biology Is (So Far) Irrelevant To Legal Regulation” argues that evolution does not provide the legal system with any useful rules or guidance.

Here’s the abstract:

Evolutionary biology – or, more precisely, two (purported) applications of Darwin’s theory of evolution by natural selection, namely, evolutionary psychology and what has been called human behavioral biology – is on the cusp of becoming the new rage among legal scholars looking for interdisciplinary insights into the law. We argue that as the actual science stands today, evolutionary biology offers nothing to help with questions about legal regulation of behavior. Only systematic misrepresentations or lack of understanding of the relevant biology, together with far-reaching analytical and philosophical confusions, have led anyone to think otherwise. Evolutionary accounts are etiological accounts of how a trait evolved. We argue that an account of causal etiology could be relevant to law if (1) the account of causal etiology is scientifically well-confirmed, and (2) there is an explanation of how the well-confirmed etiology bears on questions of development (what we call the Environmental Gap Objection). We then show that the accounts of causal etiology that might be relevant are not remotely well-confirmed by scientific standards. We argue, in particular, that (a) evolutionary psychology is not entitled to assume selectionist accounts of human behaviors, (b) the assumptions necessary for the selectionist accounts to be true are not warranted by standard criteria for theory choice, and (c) only confusions about levels of explanation of human behavior create the appearance that understanding the biology of behavior is important. We also note that no response to the Environmental Gap Objection has been proffered. In the concluding section of the article, we turn directly to the work of Owen Jones, a leading proponent of the relevance of evolutionary biology to law, and show that he does not come to terms with any of the fundamental problems identified in this article.

It’s an interesting paper, which makes a solid case that biological dispositions like step-parents being more liable to kill step-children than biological parents kill their natural children are irrelevant to the law even if (highly doubtful) true. I think of these arguments (rape is natural, for example) as Twinky defences; they advance the interests of one particular group for political or personal reasons rather than being founded on any solid evidence. It’s one thing to say that a person in a chemically induced state of automatism cannot be held responsible for their actions; quite another to say that a step-parent who kills a child is acting under some evolutionary compulsion.

That said, is evolution entirely irrelevant to the law? I suspect there is a basis for an evolutionary law; species-typical behaviours in common or ordinary environments in which they evolved are indicators of behaviours that are likely to enhance fitness. If we want a society in which all members are equally able to live a good life, where “good life” is defined as the optimal sort of life for a member of the human species, then we may want to know what that actually means, rather than trading on culturally bound intuitions, which in recent times licensed the conclusion that blacks and whites should never interbreed, that women should be housemakers only, and that relative poverty is an estimate of the biological worth of a family or lineage.

One problem I have with the evolutionary psychology crowd, at least as practised by Santa Barbara, is its unwarranted assumption that there was a single, unitary, “environment of evolutionary adaptedness”. Humans, like many large bodied mammals, have extensive ranges and diverse environmental conditions to which they adapt, and as a result our evolutionary adaptedness is a mosaic rather than a consistent process. I would go further: we are now in our “natural environment”, largely because when humans live somewhere, they construct a social environment there which is way more important most of the time than the ecological conditions in which it exists, and to which we are adapted.

Evolutionary psychology as a complement to the Santa Barbara approach, is the recognition that humans have a shared set of social and psychological dispositions which they use to create their environment (and which modifies the ecosystems in which they live, as in niche construction), and that this indicates the sort of “default” social structures we might expect to arise. Hence, we might wish to guard against some “natural tendencies” like nepotism and alliance-building that might undercut the core principles of a rule of law, like equality of access and protection. So far from excusing criminal activity, it may go to strengthening our understanding of the conditions under which it arises, and of ways to sanction against it.