Commanding the commons: Constitutional enforcement and the law of the sea

What role does enforcement play in protecting the constitutional authority of international law? Can enforcement be understood as a specifically constitutional practice? I argue here that international law has a greater capacity for constitutional enforcement than sceptical accounts have tended to acknowledge. This argument is anchored in the institutional account of the authority of law offered by Hart and developed by MacCormick. This focuses on the official or administrative perceptions as the determinant of constitutional legitimacy, which offers a way to offset the scepticisms caused by gaps in the constitutional order. This establishes constitutional enforcement as a practice centred on and legitimated by the attribution of role responsibilities, rather than on the direct application or policing of the rules. I illustrate these arguments using the law of the sea, a domain where the functional difficulties of enforcement have always presented a challenge to international law’s claim to authority.