Many studies show that supranational governance structures (SGS)—understood as international organizations or international treaties—contribute to the global diffusion of public policies. However, we still have a limited understanding of which properties of SGS hasten the number of policy adoptions. To advance this literature, we argue that SGS making legally binding and univocal claims are more likely to act as diffusion accelerators. We demonstrate the suitability of this argument through a case study of the global diffusion of mifepristone approvals, a single-purpose medicine to terminate pregnancies that has revolutionized abortion services. The analysis supports our expectation. Links to the EU and the Maputo Protocol—the only two considered SGS that make binding claims with clear implications for this policy field—hasten mifepristone approvals. By contrast, ratification of four other treaties—that do not make binding and univocal claims—and exposure to World Health Organization guidelines on medical abortion does not hasten these approvals.

中文翻译：

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超国家治理结构和政策传播的特性：以米非司酮批准为例


许多研究表明，超国家治理结构 （SGS）（理解为国际组织或国际条约）有助于公共政策的全球传播。然而，我们对 SGS 的哪些特性可以加快保单采用的数量仍然了解有限。为了推进这些文献，我们认为 SGS 提出具有法律约束力和单一的声明更有可能充当扩散加速器。我们通过对米非司酮批准的全球传播的案例研究来证明这一论点的适用性，米非司酮是一种用于终止妊娠的单一用途药物，彻底改变了堕胎服务。分析结果支持我们的预期。与欧盟和马普托议定书的关联（仅有的两个公认的 SGS 对该政策领域做出具有明确影响的具有约束力的声明）可加快米非司酮的批准。相比之下，批准其他四项条约——这些条约没有提出具有约束力和一致的主张——并接触世界卫生组织关于药物流产的指导方针并不能加速这些批准。