Institutionalists have explained international legalisation according to the design features of legal regimes. Constructivists have proposed instead that they reflect key actors’ internalisation of constructed behavioural standards. We identify the shortcomings of both approaches and combine their insights in order to overcome them. Such shortcomings are particularly evident when we move away from ‘classic’ cases such has the GATT/WTO and the EU. We focus rather on the Southern African Development Community (SADC) Tribunal, and the International Criminal Court (ICC), and argue that neither institutionalism nor constructivism can explain both their creation and subsequent significance. Pace institutionalism, states did not consent to these institutions because their design features offered clear benefits to domestic constituencies. Pace constructivism, the recent history of these courts foregrounds coercion and illustrates subsequent failures to internalise norms. We thus argue that constructivism can account for the non-coercive aspects of such institutions’ creation but not for their prospects. Whilst tactical concessions to evolving norms may explain the proliferation of international tribunals, subsequently the nature and content of legal regimes becomes highly significant. As institutionalists have stressed, such considerations can help explain the political ‘backlash’ against these and other institutions.
Legal rules, however, do not simply become effective because of states’ formal consent. The second part of our presentation foregrounds the constitutive nature of law (drawing on Stuart Scheingold), and the ‘internal’ aspects of legal rules (drawing on Max Weber and H.L.A. Hart). Scholarship on legalisation has neglected the fact that detailed legal rules only become authoritative, as distinct from mere behavioural norms, when legal officials believe in their specific dignity. Institutionalists, notably, have typically assumed this state of affairs. In our case studies, however, beliefs in law’s specific authority have been strongly contested both within and outside relevant institutions. Such challenges undermine the prospects of legalisation.
