Social Interactions and the Content of Legal Opinions

We explore the forces that determine rulings and citations within a court. Our model predicts: (1) that the presence of a social interaction between a judicial panel i and the authors of a prior judgement j increases the probability that i reaches the same decision as j and that i cites j as a persuasive authority and (2) that the presence of a political litigant in case i increases the probability that i cites j. Data from the English Court of Appeal confirm that an appeal panel i randomly assigned to work with the authors of a prior dismissal j are more likely to dismiss case i and cite the prior dismissal j as a persuasive authority than an appeal panel without such contact. These effects are stronger when panel i is more experienced and when all the authors of the prior judgement j face the prospect of promotion.