雙邊投資協定對環境治理之影響：以溫室氣體排放為實驗對象

Abstract

近年來，環境治理議題在公共行政領域受到許多注目。在國際關係的領域上，許多國際環境公約也強調了環境保護的重要性。其中，溫室氣體排放問題在環境治理相關文獻中常受探討，也有許多環境公約特別處理溫室氣體排放等問題。因此本文將溫室氣體排放視為環境治理重要議題，並將其設為本文實證模型的依變項。 不過，雙邊投資協定(Bilateral Investment Treaty, BIT)對於環境治理的影響是個新興議題，僅有少數文章討論，且討論的方向多半認為BIT對於環境確實造成影響，但未有堅實證據證明BIT約制與環境治理的相關。本文提供了實證證據，將BIT條文內容分別編碼，並以BIT約制國家的程度作為本文實證過程主要自變項，證明國家若承擔高度BIT條約義務，可能對環境治理產生負面影響。另外，由於國家仍是遵守BIT與保護環境最重要的行為者，本文將國家保障環境的意願設為重要調節變項，發現國家若有高度保障環境的意願，將會減緩BIT約制對於環境造成的負面影響，表示國家的環境意識對於環境治理相當重要。 國家遵守BIT的理由，可由國家競爭稀少資本以及聲譽兩方面解釋。而國家遵守BIT的效果，許多實證研究也證實，遵守BIT對於國家管制品質(regulatory quality)有正向助益，但也可能使國家規制權受到限制。尤其國家環境規制權受到「趨中」現象的束縛，國家環境規制權被限制在一定程度。若國家間談判BIT條文時，若能掌握條約義務的明確性(preciseness)原則，或許能在BIT保障投資人與國家環境規制權取得平衡，對國家環境治理帶來更好的發展。

Environmental governance is widely discussed by studies on government policy-making. Its importance is also stressed by numerous international environment conventions. In recent years, environmental governance also become a hotspot of international investment law studies. In particular, greenhouse gas emission is one of the most attentive subject to environmental governance studies. Governments set various regulations to ease off the worsening condition of global warming according to international environment conventions. International treaty other than environmental ones might still have an effect on environmental governance. With studies proving the positive relation between greenhouse gas emission and investors, it seems interesting to clarify the correlation between BIT and environmental governance. We conduct a series of statistical test on greenhouse gas emission and BIT. Greenhouse gas emission is taken as dependent variable, and treaty obligation of BIT is taken as independent variable. The following literature provides a proof that complying with higher BIT obligation could result in higher greenhouse gas emission. However, government’s will on environmental protection which is taken as a moderator in our models could ease the worsening environmental governance. In order to gain economic benefit, treaty parties comply with BIT obligation. Complying with BIT is proved by numerous studies to enhance the regulatory quality in a state, but it also means partial restriction of state regulatory right. Especially in the realm of environmental protection, “centering effect” constraints state environmental regulatory right in a certain condition. If states stress on the importance of the balance between environmental protection and investor protection, it’s possible to diminish the impact on environment which is brought by BIT.