法官席上的政治？美国最高法院的意识形态与策略性投票

中文摘要

在美国，最高法院大法官往往依据意识形态立场投票。其原因尚未得到充分理解。为进一步了解大法官的偏好以及最高法院决策的性质，我们区分了具有决定性作用和不具有决定性作用的投票。我们发现，当一位大法官的投票具有决定性作用时，其意识形态对其投票的预测力比通常情况下更强，尤其是当其选择会影响法律先例的明确确立时。为解释数据中这一此前未知的模式，我们构建了一个投票模型，其中大法官同时具有表达性偏好与工具性偏好。也就是说，大法官在依据案件的是非曲直作出的哪一方诉讼当事人应当胜诉的判断，与自身塑造先例的愿望之间，进行策略性权衡。

Abstract

In the United States, Supreme Court justices often vote along ideological lines. Why this is the case remains incompletely understood. To learn more about justices’ preferences and the nature of decision-making in the Court, we differentiate between votes that were pivotal and those that were not. We find that in situations in which a justice is pivotal, her ideology is even more predictive of her vote than usual, especially when her choice matters for unambiguously establishing legal precedent. To interpret this previously unknown pattern in the data, we develop a model of voting in which justices have both expressive and instrumental preferences. That is, the justices strategically trade off which litigant should prevail based on the merits of a case with their desire to shape precedent.