Seminar: Paolo Sandro – Ignorance of the law cannot excuse: on the externality of law and the ascription of legal responsibility


In legal philosophy it is generally understood that when we talk about the ‘normativity’ of law what we mean is the capacity of law to represent a reason for action, and in particular a reason justifying action. It is also usually held that we can only talk of law as being genuinely normative if the reasons for action it provides figure in its addressees’ decision-making processes, that is if they become part of what Bernard Williams (1979) has called their ‘motivational set’. In this paper I take this widespread position in philosophy of law, commonly referred to as ‘reasons-internalism’, and weigh it against a basic principle shared by most existing legal systems: that for which the ignorance of the law does not constitute an excuse from it. This principle, albeit qualified in a number of respects, still constitutes a necessary element of any working legal system without which the idea of the rule of law itself could not be upheld.

A tension then arises between these two elements, for the law purports to guide conduct by motivating agents but at the same time if these agents are ignorant of the law – and thus cannot be possibly motivated by it – they are still considered liable for not complying with what the law requires. This tension is usually reconciled by saying that law needs only to be knowable, and not actually known, to its addressees.

In this paper I argue that this solution fails to resolve the tension: if law needs only to be knowable by agents in order to be considered normative upon them and thus to ascribe to them responsibility for not abiding by it, what we are indeed saying is that the reasons for action the law purports to provide are effectively external to the agents’ mental processes, i.e. they need not be related to their motivation in any relevant sense. They might be part of their motivational sets, as they often do: but this is not necessary for the ascription of legal blameworthiness. For even if they do not play any role in an agent’s decision-making process, they still constitute the standards against which her behaviour will be evaluated and ultimately assessed.  As such, I argue in the last part of the paper, law constitutes possibly the most relevant example of reasons-externalism, which is in itself a very contested position in philosophy of action. I also contend that understanding law’s normativity as external to the agents’ decision-making processes represents a major difference in the way in which law and morality purport to work: in fact it differentiates them as related but nonetheless discrete normative enterprises.

Discussant: Lucas Miotto