The prolific literature on the relationship between the trade and environmental regimes suffers from three shortcomings. First, it myopically focuses on multilateral institutions, while the vast majority of trade and environmental agreements are bilateral. Second, when studies consider preferential trade agreements’ (PTAs) environmental provisions, they are often limited to USA and EU agreements. Third, it examines how the trade and environmental regimes negatively affect each other, leaving aside their potential synergies. Conversely, this article assesses the potential contribution of PTAs to international environmental law. Several PTAs include a full-fledged chapter devoted to environmental protection and contain detailed commitments on various environmental issue areas. One possible scenario is that countries that are dissatisfied with traditional settings for environmental lawmaking engage in a process of “regime shifting” toward PTAs to move forward on their environmental agenda. The alternative is that PTAs’ environmental provisions are the result of “tactical linkages” and merely duplicate extant obligations from international environmental law to serve political goals. We shed light on this question by building on two datasets of 690 PTAs and 2343 environmental treaties. We investigate four potential contributions of PTAs to environmental law: the diffusion of multilateral environmental agreements (MEAs), the diffusion of existing environmental rules, the design of new environmental rules, and the legal prevalence of MEAs. The article concludes that the contribution of PTAs to the strengthening of states’ commitments under international environmental law is very modest on the four dimensions examined.

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在贸易协定中谈判环境保护：制度转变还是战术联系？

关于贸易和环境制度之间关系的大量文献存在三个缺点。首先，它短视地关注多边机构，而绝大多数贸易和环境协定是双边的。其次，当研究考虑优惠贸易协定 (PTA) 的环境条款时，它们通常仅限于美国和欧盟协定。第三，它考察了贸易和环境制度如何相互产生负面影响，撇开它们潜在的协同作用不谈。相反，本文评估了 PTA 对国际环境法的潜在贡献。一些 PTA 包括一个专门讨论环境保护的完整章节，并包含对各种环境问题领域的详细承诺。一种可能的情况是，对环境立法的传统环境不满意的国家会进行向 PTA 的“制度转移”过程，以推进其环境议程。另一种选择是，PTAs 的环境条款是“战术联系”的结果，只是复制了国际环境法中现有的义务，以服务于政治目标。我们通过构建 690 个 PTA 和 2343 个环境条约的两个数据集来阐明这个问题。我们调查了 PTA 对环境法的四个潜在贡献：多边环境协定 (MEA) 的扩散、现有环境规则的扩散、新环境规则的设计以及 MEA 的法律普遍性。