A Voting Architecture for the Governance of Free‐Driver Externalities, with Application to Geoengineering

Abating climate change is an enormous international public-goods problem with a classical “free-rider” structure. However, it is also a global “free-driver” problem because geoengineering the stratosphere with reflective particles to block incoming solar radiation is so cheap that it could essentially be undertaken unilaterally by one state perceiving itself to be in peril. This exploratory paper develops the main features of a free-driver externality in a simple model motivated by the asymmetric consequences of type-I and type-II errors. I propose a social-choice decision architecture, embodying the solution concept of a supermajority voting rule, and derive its basic properties.