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.

Although a growing body of research suggests that the constabularization of the military for domestic policing is counterproductive, this increasingly prevalent policy has nonetheless enjoyed widespread support in the developing world. This study advances our understanding of the consequences of militarization for perceptions of law enforcement: whether visual features shape perceptions of effectiveness, respect for civil liberties, proclivity for corruption and acceptance of militarization in one's own neighborhood. Based on a nationally representative, image-based, conjoint experiment conducted in Mexico, the authors find that military weapons and uniforms enhance perceptions of effectiveness and respect for civil liberties, and that the effect of military uniform becomes greater with increased military presence. The study also finds that gender shapes perceptions of civil liberties and corruption, but detects no effect for skin color. The findings suggest that a central feature of militarization linked to greater violence – military weapons – is paradoxically a key factor explaining favorable attitudes, and that women can play a crucial role in improving perceptions of law enforcement.

What explains the militarization of public safety? Despite its failures, police militarization remains a popular policy. Existing scholarship has mainly focused on the police adopting military weapons and tactics but has neglected a silent but consequential type: the appointment of military members as police chiefs. Whereas the conventional wisdom points to partisanship and violence as key drivers, I argue that the militarization of police leaders responds to political motives. Based on a novel data set on 5,580 appointments in Mexico and repeated event history analysis, I find evidence of a top-down militarization sequence. Mayors are more likely to appoint military chiefs when upper levels of government and peers embrace a militarized security strategy. I further illustrate how coercive pressures and strategic incentives drive this sequence.

What are the consequences of the militarization of public safety? Governments increasingly rely on militaries for policing, but the systematic study of this phenomenon’s consequences for human rights has been neglected. NGO and journalistic accounts point to widespread violations by the military, but these snapshots do not necessarily present evidence of systematic abuse. Based on unique data on military deployments and human rights complaints in Mexico, we conduct a systematic, country-wide study of the consequences of constabularization for human rights. Following matching and difference-in-difference strategies, we find that it leads to a 150% increase in complaints against federal security forces. We also leverage deployments for disaster-relief operations and complaints against non-security institutions to show that the increase is not due to underlying conditions or higher reporting in the military’s presence. The findings have important implications for our understanding of quality of democracy and the democratic ideals of civilian policing.