Introduction
This essay examines the relationship between depth and breadth of cooperation as analysed in Downs, Rocke and Barsoom (1996). In public international law, the authors challenge assumptions that high compliance rates indicate robust cooperation. Their argument highlights a strategic tradeoff states make when designing treaties.
Core Argument on Depth versus Breadth
Depth of cooperation refers to the extent to which an agreement constrains state behaviour beyond what would occur without it. Breadth concerns the number of participating states or the scope of issues covered. Downs et al. contend that states often limit depth to secure wider participation. Consequently, shallow agreements produce high compliance yet modest cooperative gains. This dynamic arises because deeper commitments raise defection costs, prompting states to opt out or dilute obligations.
Implications for Treaty Design
The authors demonstrate that compliance data alone cannot confirm effective cooperation. Rational states anticipate enforcement challenges and therefore prefer treaties that require little behavioural change. This pattern limits the breadth of truly ambitious regimes. Empirical examples from arms control and trade agreements illustrate how modest depth facilitates broader accession while deeper provisions restrict membership.
Conclusion
Downs, Rocke and Barsoom reveal an inherent tradeoff: greater depth typically narrows breadth. The insight cautions against equating compliance with meaningful legal cooperation in international law.
References
- Downs, G.W., Rocke, D.M. and Barsoom, P.N. (1996) ‘Is the Good News about Compliance Good News about Cooperation?’, International Organization, 50(3), pp. 379-406.
