Compliance with World Trade Organization dispute rulings declined in recent years. Governments frequently accuse the Appellate Body (AB) of exceeding its mandate by relying on precedent despite having no such authority. Is this criticism fair? We use new data on over 5,000 applications of legal precedent in AB rulings to test competing hypotheses. The “legal coherence hypothesis” says that legal systems adhere to precedent because they have strong incentives to appear consistent in their rulings over time. Alternatively, the “adaptation hypothesis” says that legal systems respond to political resistance, such as noncompliance, by subtly modifying precedent. The results lend greater support to the “adaptation hypothesis.” The AB is much more likely to drift from previous rulings when those decisions failed to induce compliance. The results speak to common criticisms about the intransigence of international legal systems and the ways in which international case law evolves.

中文翻译：

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国际争端机构是否越权？重新评估世界贸易组织争端裁决

近年来，对世界贸易组织争端裁决的遵守有所下降。政府经常指责上诉机构 (AB) 依靠先例超越其职权，尽管它没有这样的权力。这种批评公平吗？我们使用关于 AB 裁决中 5,000 多个法律先例应用的新数据来检验相互竞争的假设。“法律连贯性假说”认为，法律体系之所以遵守先例，是因为它们有强烈的动机在其裁决中随着时间的推移表现出一致。或者，“适应假说”说，法律制度通过巧妙地修改先例来应对政治阻力，例如不合规。结果为“适应假说”提供了更大的支持。当这些决定未能促使合规时，AB 更有可能偏离先前的裁决。