The relationship between law and politics is close but ambiguous. There cannot be politics without legally defined institutions, and conflict over laws; there cannot be law without the political process which decides on and revises laws. The overlap between political theory considerations of the principles of justice and of institution building and legal theory is evident in the work of John Rawls and Ronald Dworkin, as well as Jürgen Habermas and Michel Foucault. Historically Hugo Grotius, Immanuel Kant, G.W.F. Hegel, and Friedrich Nietzsche, provide particularly good examples of reasoning about the foundations and history of legal and political institutions as intertwined tasks.
The relationship is ambiguous, because law refers to what endures over time in institutions independent of political control, if they are working properly, while politics is a matter of partisan struggles for power, with a constantly changing balance of interests, arguments and passions. Law is what contains that struggle within rules that prevent social disintegration, while at the same time politics is what makes those rules. Entrenched constitutions and principles of justice which are a matter of tacit consensus in the political and legal elites, and maybe in the population as a whole, provide some kind of structure to contain the possible contradictions. Explicitly entrenched and tacitly followed rules constrain both political conflict along with political interference in legal institutions and the kind of laws made by political institutions. Similar constraints ensure that judges behave in a consistent manner, which respects the decisions of other judges, and the limits of judicial interpretation in relation to the way political institutions understand laws.
One issue that has been growing since the late nineteenth century in the relation between law and politics, is that of the relation of law to the growth of the state apparatus, as more and more people have become employed by the state in administering welfare payments, and other forms of state activity. Habermas, for example, though a strong supporter of the welfare state, refers to the challenged a large welfare state poses to both law and to representative institutions. How can a large bureaucracy be adequately supervised with regard to law by the courts, or with regard to democratic will by national assemblies? In this case, law and politics are both challenged by the growth of the state body.
Another issue that has been growing for law and politics since the late nineteenth century is the growth in the number of laws. The volume of statutes has grown at at an unprecedented rate since that time, law making bodies accommodate a growing tendency for the state to regulate society and the economy. The ‘Neoliberal’ period since the 1970s has not seen a drop off in this tendency, it has even been intensified by a Neoliberal shift from state ownership of economic enterprises to regulation of the economy. There is some widespread misunderstanding about this. The Neoliberal phase may include regulation which benefits particular sectors and groups of enterprises, but this is capture of a growing body of regulation and law by sections interests, not the decline of regulation whether regulation via law of administrative means set up by law.
The associated growth in the number of laws, including subordinate administrative regulations, and in the state administrative body, since the late nineteenth century is unprecedented in the numbers, but has various precedents in the growth of law and the state. The growth of Roman law and its western rediscovery in the Middle Ages are two major precedents. Max Weber gave a classic description of the growth of centralised state in the Middle Ages in association with the growth of Civil or Roman law. Michel Foucault describes that process as well, and as part of a shift from a spontaneous individual technē (art or skill) of living to juridificaton, the imposition of law from above. What we will concentrate on here is the discussion in Friedrich Hayek and Carl Schmitt of the role of law over time, and its relation to politics (search posts from recent months for more on these issues in Hayek and Schmitt, with regard to law and legislation).