The Causes and Effects of Leaks in International Negotiations

International negotiations are founded on secrecy. Yet, unauthorized leaks of negotiating documents have grown common. What are the incentives behind leaks, and what are their effects on bargaining between states? Specifically, are leaks offensive or defensive: are they intended to spur parties to make more ambitious commitments, or are they more often intended to claw back commitments made? We examine these questions in the context of trade negotiations, the recurring form of which affords us rare empirical traction on an otherwise elusive issue. We assemble the first dataset of its kind, covering 120 discrete leaks from 2006 to 2015. We find that leaks are indeed rising in number. Leaks are clustered around novel legal provisions and appear to be disproportionately defensive: they serve those actors intent on limiting commitments made. The European Union (EU) appears responsible for the majority of leaks occurring worldwide. Using party manifesto data to track changing ideological positions within the EU, we find that the occurrence of leaks correlates with opposition to economic liberalization within the average EU political party. Moreover, leaks appear effective in shifting public debate. We examine trade officials' internal communications and media coverage in the wake of a specific leak of negotiations between Canada and the EU. A given negotiating text attracts more negative coverage when it is leaked than when the same text is officially released. In sum, political actors leak information strategically to mobilize domestic audiences toward their preferred negotiating outcome.