The rule of law as a globally recognised concept is multi-faceted (Chesterman, 2008). In the common-law tradition, it is conceived through a formal and substantive framework. In essence, it centres on the supremacy of the law over the arbitrary exercise of power and the formal legality of the law (Tamanaha, 2004, p. 115; Cotterrell, 1992, p. 157). The rule-of-law concept has been criticised as being of unique European origin, where plural social organisation and universal natural law constitute its two preconditions (Unger, 1977, pp. 80–110). It has, however, been advocated around the world as one essential principle leading to modernity, where the legitimacy of the law based on the formal and substantive rule of law serves as a strong symbol for a modern society (Deflem, 1996, p. 5).