Jana von Stein is a Senior Lecturer in Political Science and International Relations at Victoria University of Wellington (New Zealand) and a Faculty Associate at the Center for Political Studies (University of Michigan)] When do – and don’t – states comply with international rules? For instrumentalists (adopting Keohane’s –admittedly simplified– categorization of the literature as ‘instrumentalist’ and ‘normative’, the puzzle starts with the observation that no overarching power exists to enforce international law. If there is no ‘highest power’ to enforce rules, why follow them? The ‘engines of compliance’ are typically more diffuse than in domestic systems, but they are nonetheless real:
- International inducements. Sometimes a state benefits enough from having others follow the rules that it pays the ‘cost’ of ensuring compliance itself, whether in the form of ‘carrots’ (e.g., trade concessions) or ‘sticks’ (e.g., economic sanctions). Inducements are typically decentralized and based on self-help, so their application can be uneven. Inducements also face typical collective action problems, and so often work best when a powerful state is doing the heavy lifting.
- Reciprocity. Axelrod demonstrated long ago that reciprocity can be an engine of cooperation if the involved parties are sufficiently sure that they will interact into the future. The same logic holds for compliance, under certain conditions. Reciprocal noncompliance must harm the party that is tempted to renege: this is why (direct) reciprocity is rarely useful in international human rights law, but can work in the realms of trade and war conduct. Reciprocity is also problematic if the ‘punishment’ can’t be limited to the violator, as is often the case in international environmental affairs.
- Reputation. For instrumentalists, reputation is a means to an end: a reputation for keeping promises can make it easier to secure cooperation more broadly or in the future. Reputation is important for predicting future behavior, not for punishing past actions. Scholars debate just how much reputation carries over from one issue-area to another, or from one government administration to another. What is more, concerns about reputation can sometimes push governments not to comply, for instance if they want to foster a reputation for protecting their interests or their friends.