Observers of post-Communist politics recognize that civil service reform, an important part of the institutional transformation in Eastern Europe, was initiated at a very uneven pace. Hungary and Poland adopted changes quickly after the fall of Communism, while Romania and Slovakia waited longer. How can one explain the timing of civil service reform after 1989? Previous research blames a number of factors but inconsistencies between predictions and actual outcomes warrant a more thorough investigation. What has been overlooked, we argue, are the policies of transitional justice that altered the costs and benefits for elites to keep the institutional status quo. The empirical analysis reveals that when in place, lustration by vetting of public officials reduced the likelihood of passing a civil service reform act. This effect is conditioned by the legislative strength of ex-Communist parties, as demonstrated by results from logistic regression tests on data from 11 countries.