Crime and violence have made public security a major concern to voters throughout Latin America. Existing research predicts that such widespread concerns should make public security a consistently successful issue in presidential election campaigns. Yet recent empirical reality in Latin America has been more varied. This study argues that success on public security is not so automatic. Human rights concerns combine with low trust in security forces to make success on security contingent on the correct conditions. Two key conditions affect the use of the issue: the degree to which security threats are organized and the degree to which recent repression has occurred. Then, winning votes depends on two further conditions: having a civilian background and a campaign that balances security with other issues. Together, these factors explain the dramatic variation in success, and suggest a key change from Latin America's past.