摘要： 联邦制很可能不会产生一些学者预期的制度效果。联邦制有其消极法治后果，自有成因。诱导联邦制的积极法治效果，需要两个必不可少的政治条件：首先是发达的民主，其次是竞争性的政党政治。在充分的政党竞争的前提下，民主的提升，对于联邦制国家的法治有促进作用。无论是基于面板数据的分析，还是运用横断面数据的稳健性检验，都为此理论假设提供了有力支持。对于那些筹谋联邦化现有政治结构的国家而言，政策制定者需要特别谨慎，因为在其他重要制度条件欠缺的情形下，这样的垂直权力分配结构的变化，将很难达成预期目标，反而可能使情况变得更糟。

关键词: 联邦制, 民主, 政治分化, 法治, 定量研究

Abstract: Federalism is very likely to generate effects that contradict conventional theoretical expectations. This article focuses on how federalism affects the rule of law, detailing the reasons why federalism could exert negative influences on the rule of law, and intending to identify the political conditions under which federalism is conducive to the betterment of the rule of law. Building on the existing research, the author proposes two conditions: one is high democracy, and the other is greater degree of governmental fractionalization. It has been presupposed that given the sufficient party competition, federalism tends to strengthen the rule of law as the democratic enhancement is increasingly made. Both panel data analysis and cross-sectional robustness test lend support to the hypothesized theory. This article contributes not only to the literature of decentralization but also to the quantitative study of determinants of the rule of law. Last but not the least, as far as the policy is concemed, political elites should stay more cautious when they attempt any political change in the anticipation that the reconstruction of power structure in vertical dimension by merely federalizing will invariably lead to the Pareto improvement, because as this paper shows, federalism alone can hardly introduce desired progress, if not makes things worse.

Key words:  Federalism, Democracy, Partisan Fragmentation, Rule of Law, Quantitative Study