This paper seeks to explain why some investor-state dispute cases are settled before reaching the ruling stage in democracies, focusing on disputes triggered by regulatory changes made by host government. Our argument is grounded in the domestic politics of the respondent country, specifically the partisan orientation of the incumbent government. When faced with regulatory investor claims, respondent governments must balance protecting domestic social welfare with promoting investment. Our theory is that right-leaning governments are more likely to settle because they are more willing to make regulatory concessions to appease foreign investors and attract investment. In contrast, left-leaning governments prefer arbitral rulings over settlements, as they view settlements as a capitulation to foreign investors’ demands at the expense of public welfare. Using original data from 335 investor-state disputes involving democratic host countries between 1994 and 2020, we find support for this claim. Moreover, we provide qualitative evidence from the investor-state dispute between TC Energy Corporation, a Canadian energy company, and the United States, as well as the investor-state disputes triggered by Argentina’s 2002 emergency measures, to confirm our hypothesized causal pathway linking government partisanship to the likelihood of settlement.

本文试图解释为什么在民主国家，一些投资者与国家之间的争议案件在进入裁决阶段之前就得到了解决，重点关注由东道国政府的监管变化引发的争议。我们的论点基于被诉国的国内政治，特别是现任政府的党派取向。当面临监管投资者的索赔时，受访政府必须在保护国内社会福利和促进投资之间取得平衡。我们的理论是，右倾政府更有可能安定下来，因为它们更愿意做出监管让步来安抚外国投资者并吸引投资。相比之下，左倾政府更喜欢仲裁裁决而不是和解，因为他们认为和解是以牺牲公共福利为代价向外国投资者的要求投降。使用 1994 年至 2020 年间涉及民主东道国的 335 起投资者与国家争端的原始数据，我们找到了支持这一说法的支持。此外，我们还提供了来自加拿大能源公司 TC Energy Corporation 与美国之间的投资者-国家争端以及阿根廷 2002 年紧急措施引发的投资者-国家争端的定性证据，以证实我们假设的将政府党派关系与和解可能性联系起来的因果途径。