What are the political consequences of militarizing law enforcement? Across the world, law enforcement has become increasingly militarized over the last three decades, with civilian police operating more like armed forces and soldiers replacing civilian police in law enforcement tasks. Scholarly, policy, and journalistic attention has mostly focused on the first type, but has neglected the study of three main areas toward which we seek to contribute: 1) the constabularization of the military—i.e., when the armed forces take on the responsibilities of civilian law enforcement agencies, 2) the extent to which this process has taken place outside of the United States, and 3) its political consequences. Toward this end, we unpack the concept of militarized law enforcement, develop theoretical expectations about its political consequences, take stock of militarization in Latin America, and evaluate whether expectations have played out in the region. We show that the distinction between civilian and military law enforcement typical of democratic regimes has been severely blurred in the region. Further, we argue that the constabularization of the military has had important consequences for the quality of democracy in the region by undermining citizen security, human rights, police reform, and the legal order.