(corresponding author)

We formulate a new game-theoretic model of bargaining on the U.S. Supreme Court. In the model, a degree of monopoly power over policy endogenously accrues to the assigned writer despite an open rulepermitting other justices to make countero¤ers. We assume justices are motivated ultimately by a concern for judicial policy, but that the policy impact of an opinion depends partly on its persuasiveness, clarity, and craftsmanship its legal quality. The e¤ort-cost of producing a high quality opinion creates a wedge that the assignee can exploit to move an opinion from the median without provoking a winning counter-o¤er. We use this bargaining model as the foundation for a formal analysis of opinion assignment. Both the bargaining and opinion assignment models display rich and tractable comparative statics, allowing them to explain well-known empirical regularities as well as generate new propositions, within a uni\u85ed and internally consistent framework