Chiman Cheung, UC Berkeley

Information can spur community collective action against environmental harms, but its effectiveness depends on how it is delivered and by whom. Local leaders can legitimize and transmit new information, or distort and suppress it when incentives misalign. We study these trade-offs in the context of artisanal and small-scale gold mining (galamsey) in Ghana. In a cluster randomized controlled trial across 99 galamsey communities, stratified by leader conflicts of interest, we screened a documentary on mercury’s health risks either privately to leaders (traditional local chiefs) or publicly to both leaders and community members. Leader-only screenings improved health-risk learning among chiefs but had no detectable effects on community learning, preferences for local mining rules, or collective action participation. Public screenings, in contrast, increased community learning and participation, as reflected in higher sign-ups for regular assembly meetings and more frequent community discussion of galamsey. When paired with non-conflicted leaders, public screenings shifted community preferences toward stricter mining bylaws, whereas under conflicted leaders, they instead polarized these preferences. Together, the results suggest that building consensus and mobilizing community collective action requires both an informed public and non-conflicted leadership; neither alone is sufficient.