LAW, LEGITIMACY AND SEPARATION OF POWERS

• Citation: (2017) 29 SAcLJ 941
• Author: Kevin Y L TAN LLB (Hons) (National University of Singapore), LLM, JSD (Yale); Adjunct Professor, Faculty of Law, National University of Singapore.
• Date: 01 December 2017
• Published date: 01 December 2017

This article argues that for the separation of powers doctrine to work, it is not enough that we consider what the relevant branches of government are or how power is to be distributed between them. What most scholars seem to have ignored is the need for constitutions to take into account and bring under the law, all legitimate forms of power within a polity. Unless this is done, such extraconstitutional sources of power may supplant the constitutional order because of the greater legitimacy it enjoys, outside the constitutional framework.

I. Getting beyond Montesquieu

1 “Constitutionalism”, said Charles McIlwain, “has one essential quality: it is a legal limitation on government”.1 Political thinkers have long known what Lord Acton was to memorably articulate in – while power tends to corrupt, absolute power corrupts absolutely. As Scott Gordon observed:2

The thesis that power corrupts its possessor may be as good as a ‘law’ as any that we have in political science, but the emergence of states in which political power was significantly distributed among competing institutions antedates feudalism and capitalism in Europe. The need to control the exercise of state power, and the notion that it can be done by institutional design, is evident in the political systems of Periclean Athens and republican Rome. The idea of a ‘constitutional’ order has a provenance as old as Western political thought …

2 How do we limit state power through the constitution? The English political philosopher John Locke thought that this could be done by dividing up state power. In his Two Treatises of Government (1690), he advocated separating the legislative power from the executive power to prevent government from becoming arbitrary and tyrannical.3

3 The French philosopher Charles-Louis de Secondat – better known as Baron de Montesquieu – developed Locke's proposition further and evolved the now classic formulation of the doctrine of the separation of powers. In Book XI of his De L'esprit des Lois (On The Spirit of the Laws), he posited that in every government, “there are three sorts of power: the legislative; the executive in respect of things dependent on the law of nations; and the executive in regard to matters that depend on the civil law”.4 And, if “the legislative and executive powers are united in the same person, or in the same body of magistrates, there can be no liberty; because apprehensions may arise, lest the same monarch or senate should enact tyrannical laws, to execute them in a tyrannical manner”.5 There can also be no liberty if the Judiciary was not independent of the other two branches:6

Again, there is no liberty, if the judiciary power be not separated from the legislative and executive. Were it joined with the legislative, the life and liberty of the subject would be exposed to arbitrary control, for the judge would then be the legislator. Were it joined to the executive power, the judge might behave with violence and oppression.

There would be an end of everything, were the same man or the same body, whether the nobles or of the people, to exercise those three powers, that of enacting laws, that of executing the public resolutions, and of trying the causes of individuals.

4 Montesquieu's theory was indeed attractive. Divide up or separate all of the state power functionally into three branches, each with its own responsibility and sphere of operations. In doing so, one can ensure that power is not centralised in any one of these branches of government, thus preventing all power from being centralised or concentrated in one person or body. While Montesquieu purported to be describing a form of government – that of England in this case – rather than prescribing one, his observations on the separation of powers was to acquire the status of doctrine shortly after his On The Spirit of the Laws was published in 1748. M J C Vile, in his classic Constitutionalism and the Separation of Powers,7 argued that

Montesqueiu's tripartite conception has remained so influential largely due to the timing of its publication.8

5 In the next few decades, On The Spirit of the Laws would become a key reference work for revolutionaries in France and in America who were casting about for new models of government to replace those of the ancien regime. The logic of the separation of powers was nowhere better operationalised than in the Constitution of the United States of 1787.9 Montesquieu did not, however, advocate a “pure doctrine” of the separation of powers that required each branch of government to “be confined to the exercise of its own function” and not be “allowed to encroach upon the functions of the other branches”.10 Instead, he favoured a partial separation of powers by having certain powers shared between the different branches. In that way, it is possible for one branch to check another to achieve balance in governance.11

6 Over the next two centuries, Montesquieu's tripartite classification remained largely unchallenged. Constitution makers were content to accept that the sum total of state power fit, more or less neatly, in this classification and debates about constitutional design – in so far as the separation of powers is concerned – the manner in which powers ought to be divided.12 Should more power be given to the Executive or the Legislature? Who should rightly have the power to make treaties, or make law? Should a powerful unicameral legislature be divided further by the creation of a second chamber?

7 Major criticisms of Montesquieu's doctrine fall into two broad categories. The first lot of critics attack Montesquieu for his flawed description of the English model of constitutionalism and consequently for the irrelevance of this doctrine to British practice.13 The second

category of criticisms concern the difficulty in classifying the various types of powers exercised by public bodies and institutions. Indeed, the problems of classification – as to whether a new institution or “power” is properly classified under “legislative” or “executive” – has dominated critiques of the Montesqueiu doctrine. Even Bruce Ackerman, one of Montesquieu's most trenchant modern critics, continues in the same vein.14 Ackerman argued that no “field of academic inquiry” has been “so dominated by a single thinker”, especially one from the 18th century who “did not have the slightest inkling of political parties, democratic politics, modern constitutional design, contemporary bureaucratic techniques, and the distinctive ambitions of the modern regulatory state”.15 He continued:

Almost three centuries later, it is past time to rethink Montesquieu's holy trinity. Despite its canonical status, it...