Public policies and global forest conservation: Empirical evidence from national borders

Protecting the world's remaining forests is a global policy priority. Even though the value of the world's remaining forests is global in nature, much of the protection has to come from national policies. Here, we combine global, high resolution remote sensing data on forest outcomes (tree-cover loss, forest degradation, net primary production) and two complementary econometric research designs for causal inference to first quantify how much it matters in which country a forest is located, secondly, the role of public policies, and third, under which conditions such pubic policies tend to be most successful. We find considerable border discontinuities in remotely sensed forest outcomes around the world (in a regression discontinuity design) and these are largely explained by countries' policies (using a differences-in-discontinuities design). We estimate that public policies reduce the risk of tree cover loss by almost 4 percentage points globally, but there is large variation around this. The best explanations we find for these heterogenous treatment effects are a country's policy enforcement, its policy stringency, its property rights, and its rule of law (in that order). Our results motivate international cooperation to finance and improve (a) countries' public policies for forest protection and (b) countries' capacity to implement and enforce them well.