強化氣候變遷減緩的國際義務 ── 從氣候人權訴訟到國家責任法框架

Abstract

國際氣候變遷治理體系主要由《聯合國氣候變遷綱要公約》、《京都議定書》及《巴黎協定》等國際氣候條約所構築。這樣的治理體系縱然獲得國際社會的廣泛支持，卻因缺乏法律拘束力、強制力與有效監督機制等問題，使國際間溫室氣體減量管制成效不彰，並飽受各界批評。近年來，全球暖化與氣候變遷不斷惡化，促使國際社會開始在氣候條約之外尋找新的氣候變遷治理規範，基此背景，國際間興起一波以國家人權義務為基礎，主張國家氣候變遷減緩政策與措施未能達成國際減排承諾與目標的氣候人權訴訟。本文聚焦氣候變遷減緩的國家義務，探討近年歐洲人權法院與聯合國人權公約機制中的氣候人權訴訟案件，分析氣候變遷對人權的影響與威脅，以及氣候人權訴訟中常見的當事人適格、因果關係、與作為義務標準等訴訟問題。本文發現，近年來的氣候人權訴訟標誌著氣候條約體系橋接具拘束力且提供救濟途徑的人權規範體系的趨勢，氣候減緩的義務以積極人權義務為載體，形成了氣候條約外的治理機制。承接此強化國際氣候條約減緩義務的需求，又鑑於氣候人權訴訟中未解的訴訟障礙，本文進一步提出在氣候條約與國際人權法體系外，從一般國際法之國家責任法框架，強化氣候變遷減緩國際義務的可能性。本文認為，透過《巴黎協定》下的氣候變遷減緩目標與義務，結合氣候人權訴訟中所觀察到的減緩義務之人權保護效力與關聯性，可以建立以《巴黎協定》核心減緩條約義務為「對締約國整體義務」，進而從一般國際法層次強化條約義務效力的論述。並且，透過國家責任法原理原則與案例，能舒緩在國家責任法框架中提起氣候變遷減緩國際訴訟所面對的因果關係舉證難度，亦能在一定程度上避免人權法院與申訴機制中嚴格的訴訟程序要件限制。從一般國際法層次，透過國家責任法框架與《巴黎協定》條約義務建立之氣候變遷減緩國際義務，能在既有的條約義務下與人權法規範外，進一步強化既有氣候條約義務之拘束力與國家氣候責任問責性，形成更全面且完善的國際氣候變遷減緩治理圖像。

The international climate change treaty regime, primarily constructed of the United Nations Framework Convention on Climate Change, the Kyoto Protocol, and now the Paris Agreement, has received widespread support and is considered a political success within the international community. However, the treaty regime faces criticism for its lack of binding substantive mitigation obligation, and its ineffective legal mechanisms for enforcement, supervision, and accountability, which results in insufficient greenhouse gas emission control and the aggravation of global warming. The severity and urgency of climate change in recent years have prompted the need to seek new regulatory mechanisms for climate change governance beyond climate treaties. Against this backdrop, there has been a surge in rights-based climate litigation globally. Based on human rights obligations, litigants turn to courts to challenge the overall efforts of a State to mitigate climate change by alleging that its domestic mitigation policies and measures fail to achieve the goals and commitments acknowledged in international climate treaties and, among other focuses, States’ obligations to ensure the enjoyment of fundamental human rights such as the right to life and self-determination. This paper focuses on international obligations on climate change mitigation. While exploring recent rights-based climate litigation cases within the European Court of Human Rights and the United Nations human rights mechanisms, this paper analyzes the impact of climate change on human rights and the common hurdles in rights-based climate litigation, such as standing/victim status, causation, the requirement of exhausting local remedies, and the standards of care of obligations to mitigate risk and harm posed by climate change to the enjoyment of human rights. This paper finds that recent rights-based climate litigation marks a trend of bridging climate treaty regimes with the framework of human rights law. The international obligation of climate change mitigation, carried as positive human rights obligations, forms a new governance scheme outside international climate treaties. In response to this shift of regulatory forum and considering unresolved hurdles in rights-based climate litigation, this paper further proposes to reinforce the climate treaty regime, particularly the Paris Agreement, by establishing international obligations for climate change mitigation within the framework of the law of state responsibility. This paper suggests that by integrating the mitigation goals and obligations under the Paris Agreement with the efficacy and relevance of human rights protection observed in rights-based climate litigation, it is possible to establish core mitigation obligations under the Paris Agreement as obligations erga omnes partes. This would form a binding and substantive mitigation obligation under the Paris Agreement, which in turn creates a narrative for standing to initiate climate litigation in the International Court of Justice (ICJ). Moreover, through the law of state responsibility, the burden of proving causation and satisfying strict procedural requirements in rights-based climate litigations can be alleviated. Identifying substantial international obligations on climate change mitigation under the Paris Agreement through the framework of the law of state responsibility, not only allows for a malleable and flexible application of various international obligations, but also reinforces climate change mitigating obligations under the treaty regime, and facilitates mitigation accountability within climate treaties and beyond human rights norms, thereby establishing a more comprehensive and robust international climate change mitigation governance regime.