The Edge of the Range
Let us suppose then that we have hit upon a moral interest driving the specification of personhood as a range property. A difficult question still remains. What is
- 18 ibid 556.
- 19 ibid 557.
that absolute minimum threshold above which the range property specification applies? In most discussions about human equality, as I noted, it is assumed that the boundary-line is birth. But why does ‘opacity respect’ begin here, not sooner or later? Presumably, the interest driving the need to specify a range does not necessarily specify how that range ought to be marked out. Carter presents a persuasive argument for regarding personhood as a binary property above a minimum threshold, but it is not yet clear why that threshold could not be conception, viability, or some time during infancy, rather than birth.
As I have said, defenders of the species membership criterion for personhood share the ‘range property’ intuition, but take that range to be bounded by genetic humanity rather than birth. Should opacity respect not include fetuses, along with born human beings? The species membership argument might be helped along here by the popular claim that there is no morally significant difference between a very late fetus and a neonate that could explain or justify placing personhood’s minimum threshold at birth.
The question then turns to the reasons which exist for stipulating the threshold in one place rather than another. To stipulate it at conception seems unsatisfactory given just how far away such organisms are from the sort of creatures that exemplify the base properties of personhood. Of course, wherever the threshold for full moral status is placed will be arbitrary in at least the sorites sense. This cannot be avoided. But there is no requirement to avoid that kind of arbitrariness unless one thinks that the threshold must aim at correspondence with a sudden metaphysical leap into personhood—a suggestion that I have argued lacks credibility.
When it comes to the law in particular, Timothy Endicott has set out some of the reasons why vagueness surrounding legal thresholds cannot be completely elimi- nated. In fact, he argues, it is not clearly the case that vagueness entails a deficit in rule of law standards, or leads to arbitrariness in the pejorative sense. Endicott distinguishes four different forms of arbitrariness in governance. The law can be arbitrary when it: 1. ‘gives effect to the unconstrained will of the rulers’; 2. does not treat like cases alike; 3. is unpredictable; or 4. when its provisions depart from what Endicott calls ‘the reason of the law’, by which he means the principles contained within the law.
Endicott’s main point is that it is impossible for the law to perfectly uphold all of these standards. Moreover, much of the time, reducing arbitrariness in some respects may only increase it in others. For instance, making laws more precise, and hence more predictable, might require departing from the reason behind the law. He gives the example of a time limit of precisely seven months for the prosecution of serious criminal offences. A strict seven-month cut-off would result in permitting some prosecutions which, according to the rationale for the limitation, should really not be permitted, and precluding some that ought to be. This is an inevitable result of there being no meaningful difference between cases immediately on one side of the line or the other.
A precise legal threshold of personhood is not arbitrary in any of the senses one to three. But increasing precision can increase arbitrariness in the fourth sense by stipulating boundary-lines which ‘do not reflect the reasons on which such a law ought to be based’, like the reasons for or against prosecuting a crime.21 The more precise a boundary is, the less likely that one can adduce a legal reason for placing the line right there. Increasing precision can require determinations to be made between adjacent points when there is no ‘reason of law’ for choosing between them. Given the sorites problem, it might be argued that every legal threshold is arbitrary in this fourth sense. No threshold can be non-arbitrarily distinguished from its very closest neighbouring points using principles of law.
So a legal threshold of personhood is not unacceptably arbitrary merely because it is sorites-susceptible. It may depart from the rule of law in being too precise to follow or to consistently enforce, or, indeed, too vague. This sets down some basic standards of clarity and practical usability for the legal threshold of personhood. A law which stipulates the beginning of personhood down to the millisecond will not be a good guide for conduct, even if it can just about be followed.
Some favour birth as a legal threshold for precisely these kinds of reasons: birth is a highly visible event, it is not speculative, and it is an easy guideline with which to comply. Other milestones, both post- and ante-natal, are somewhat less transparent and much easier to mistake or conflate with earlier and later developments, such as the acquisition of viability in utero, or of self-awareness post-birth. As Endicott helps to explain, considerations like clarity are not extra-legal, given that the need for clear resolution is itself a concern of the law. The only condition on the stipulated threshold is that it is within the range of acceptable solutions.
According to Endicott’s standard, therefore, the only question we need ask is whether there is a decisive reason against stipulating birth as the threshold of fully realized personhood. Not only do I think that no such reason against birth as a legal resolution exists; there are, moreover, compelling reasons in favour of equating birth with the entry into the personhood range. Those reasons derive from the birth threshold’s practical workability and its importance for some of the basic conditions of personhood.
-  Timothy Endicott, ‘The Impossibility of the Rule of Law’ (1999) 19 Oxford Journal of LegalStudies 1.