Using cross-sectional data, studies of the relation between merit-based bureaucracies and corruption usually find that nations with more professional and politically independent bureaucracies have lower corruption. However, cross-section designs cannot test this policy claim. This study adopts a pre-test‒post-test design using lagged data comparing changes in civil service laws and implementation in eight Latin American countries from 2004 to 2012 and data reporting subsequent change in bribe requests by the bureaucrats that the laws are intended to affect. Raising questions about the validity of previous results, it is found that improved laws and implementation were associated with no or increased bribe requests.