Philosophy of law has long been in a state of deadlock, unable to make progress in solving the puzzle of law’s authority – that law is both a matter of right and might. This book seeks to break the deadlock.1 It does so by going back to the work of HLA Hart, who in 1958 set solving that puzzle as the main task for legal theory in ‘Positivism and the Separation of Law and Morals’ with his lapidary claim: ‘Law surely is more than the gunman situation writ large’.2 I argue that the task can be accomplished through exploiting the rich resources in Hart’s own legal theory. But I do so in a way closed to him by the idea he claimed was central to his tradition in his 1958 manifesto for legal positivism: his Separation Thesis that there is no necessary connection between law and morality.

Most readers acquainted with Hobbes will think that a chapter on Hobbes and the puzzle of very unjust law must be rather short. After all, Hobbes is infamous for arguing that the law the sovereign makes not only can have any content but also that the content it happens to have is by definition just. He thus seems to have offered a radical version of a one-system theory about the relationship between law and morality in which morality is collapsed into the content of the positive law of a particular jurisdiction. Moreover, in a well-known passage, he explicitly denied the existence of such a thing as fundamental law, thus excluding a role for fundamental principles of legality in his legal theory.1 In short, he seemed to rule out the kind of puzzle of very unjust law which we saw in Chapter 1 flummoxed both Hart and Dworkin.

Central to philosophy of law, I have argued, is the legal subject’s question ‘But, how can that be law for me?’ Chapter 4 explored that argument in an investigation of the interaction between the space of the modern legal state and law ‘beyond the state’. Here I investigate the difference made to the answer to the question when it is given in two different contexts: first, a context in which a legal space – one both constructed by law and ruled by law – interacts with another legal space; and, second, in a context in which a legal space interacts with a space of no-law. As we will see, the definition of a legal space as both constructed by law and ruled by law is important because law can be used to construct a space of no-law, a legal void or ‘black hole’, as Lord Steyn described the situation of detainees at the US base of Guantanamo.1 In such a space, prerogative or legally unmediated power rules.

In Chapter 3, I discussed the complicated relationship between constitution as act and constitution as achievement, as well as the idea that the constitution is greater than the sum of its parts. This chapter focuses on the remaining issue which complicates our understanding of constitutionality – its Janus-faced nature. The act of constitution, that is, looks both inwards and outwards.

In this chapter, I bring together the themes explored in the preceding chapters. In particular, I elaborate the main implication of Dworkin’s remark in the manuscript version of Justice for Hedgehogs that it would be counterintuitive to think that ‘most of the subjects of most of the political communities over history had no moral duty to obey the laws of their community’.1 As I suggested at the end of Chapter 1, the implication is that the moral record of the law of a society, the fund of values in fact established over time, amounts to what Hobbes told us is ‘the publique Conscience, by which … [the subject] hath already undertaken to be guided’.2

In the short chapter ‘Law’ in Justice for Hedgehogs, Ronald Dworkin said that ‘the puzzle of evil law’ has had a ‘prominent place in seminars on legal theory’ although it is of ‘almost no practical importance’.1 The puzzle, in his view, is primarily about cases where judges find themselves faced with the problem of enforcing an evil law. Should we say that the judges must not enforce it because it is very unjust, or that they must not enforce it because it is not law? Since philosophers of law agree on the practical outcome – judges must not enforce evil law – Dworkin claimed that the ‘ancient jurisprudential problem is sadly close to a verbal dispute’.2