Do radical anticorruption measures such as lustration reduce corruption by systematically limiting the political participation of former authoritarian actors? While research has largely overlooked the role of transitional justice in addressing corruption, some scholars claim that lustration may increase corruption by reducing bureaucratic expertise. Analyzing original panel data from 30 post-communist states from 1996 to 2011, we find that lustration is effective in lowering corruption. Lustration disrupts the political, economic, and administrative malpractice of the preceding regimes by limiting opportunities for corruption of former communist elites. To illuminate the causal mechanism, we examine the cases of Estonia, which has adopted lustration and lowered corruption; Georgia, which has reduced corruption since first considering lustration; and Russia, which has not adopted lustration and maintains high levels of corruption. This study breaks new ground with a novel system-level explanation and an integrative approach to causation for the entire post-communist world.Corruption in the former communist world represents a major problem for policy makers and scholars alike. Whether in the form of administrative malpractice, asset stripping, or state capture, post-communist corruption has been pervasive and difficult to fight (Karklins 2005). As a theoretically driven problem, studies on corruption have boomed, but anticorruption research remains Ba young métier^(Schmidt 2007). The St Comp Int Dev impact of the anticorruption efforts is ambiguous (Sampson 2010) and the lack of theoretical debate limits research progress.Particularly puzzling is the absence of a major theoretical issue: the impact of transitional justice. If purging corruption is a matter of justice and integrity in societies after a regime change (Anechiarico 1996), why have scholars been silent on whether transitional justice affects post-communist corruption? There have been countryspecific studies regarding the impact of international banks and organizations (Michael 2004), domestic anticorruption agencies, civil society, and the media (Hough 2013) on corruption. However, little research has assessed the mechanisms of transitional justice as anticorruption tools.Lustration is analogous to the transparency and anticorruption legislation that screens politicians for unethical behavior (Alt et al. 2006) and has been viewed as a radical anticorruption measure (Holmes 2006). As a form of social and administrative justice, lustration scrutinizes individuals for links with the previous authoritarian leadership, bureaucracy, or security services and limits their political and civic participation. While it has been often used as a tool for political competition rather than justice (Rožič 2012), we find that lustration coincides with low levels of corruption. Using the discourse of the past to justify lustration against political opponents, political elites reduce corruption when they debate and implement lustration. This correlation raises the unaddr...