Between August 10 and 15, the first cohort of the Public Security Leadership Academy participated in an immersion program in Medellín, Colombia. Organized by Leme in partnership with FGV EBAPE and Universidad EAFIT, the program brought together classes, field activities, technical visits, and meetings with researchers, public officials, and professionals from different Colombian institutions.

Why Medellín?

In the 1990s, Medellín recorded as many as 395 homicides per 100,000 inhabitants, making it one of the most violent cities in the world. In 2025, this figure had fallen to 13, one of the most significant reductions in lethal violence ever documented in a major city.

This decline, however, did not eliminate criminal groups: more than 400 combos still control territories and collect extortion payments across the city. Even so, Medellín maintains high levels of movement among residents and tourists, active commerce, and functioning public services, including in areas where these groups have a strong presence. This reduction in homicides resulted from an integrated approach combining security policies, institutional strengthening, and urban and social interventions.

Medellín is therefore a rare case: a city that drastically reduced lethal violence without eliminating organized crime and that now coexists with it without allowing it to paralyze urban life. It was this trajectory, including the city’s strategies, results, limitations, and challenges, that the program’s students went to examine firsthand. The goal was not to reproduce a “Medellín model” in Rio de Janeiro, but to broaden participants’ range of perspectives for thinking about solutions suited to the state’s reality.

Throughout the week, classes and sessions were led by researchers and experts with different perspectives on public security and crime, including Santiago Tobón, Gustavo Duncan, Miguel La Rota, Felipe Martínez, Andrés Preciado, Sergio Urán, Alejandro Gómez, and Michael Weintraub. The diversity of academic and professional experiences enabled participants to discuss the challenges of Colombian public security from different perspectives, combining research, knowledge of the local context, and institutional experience.

Organized crime and territorial control: understanding before confronting

One of the main themes of the immersion was understanding how organized crime actually organizes itself and controls territory in Colombia. The classes addressed the formation and transformation of armed groups, the different forms of drug trafficking activity, and the mechanisms of control exercised by criminal organizations in urban and rural contexts.

Based on this diagnosis, participants learned about the institutional responses developed to address these challenges: surrender agreements used by Colombia, experiences of negotiation and demobilization of armed groups, and municipal initiatives to measure and address criminal economies such as extortion and drug trafficking.

Criminal justice, data, and prevention

The immersion also provided an opportunity to learn about different dimensions of the Colombian criminal justice system. The classes covered Criminal Law and Criminal Procedure, criminal prosecution strategies, and negotiation processes conducted by the state with armed groups. At the Fiscalía Nacional, an institution broadly equivalent to Brazil’s Public Prosecutor’s Office, participants visited the forensic department and learned about SUCOBA, a ballistic comparison system used in forensic investigations.

Michael Weintraub, a professor at Universidad de los Andes and a researcher affiliated with Leme, presented evidence on police trust and legitimacy, discussing practices capable of strengthening this relationship, from neutral interaction protocols to Brazilian experiences such as body-worn cameras used by the Military Police of São Paulo and the activities of RAIO, a specialized unit of the Military Police of Ceará, whose effects also extended to public trust in the police.

Part of the group also took part in a meeting with representatives from Medellín’s Secretariats of Security and Youth, who presented the Parceros program, aimed at preventing violence and the involvement of children and adolescents in criminal activities through an integrated and multidimensional approach.

Lessons from Medellín for Rio’s challenges

The connection between the Colombian experience and the challenges facing Rio de Janeiro was present throughout the immersion and gained strength during the debriefing session held on Friday (14). After four months of training and a week of shared experiences in Medellín, participants discussed the main similarities and differences between the two contexts and reflected on how the lessons from the trip could contribute to the projects developed throughout the program. The exchange among professionals from different institutions led to adjustments to the final projects and reinforced the importance of integrated action among the Public Prosecutor’s Office, Civil Police, Military Police, and Judiciary.

Medellín beyond social urbanism

The focus of the immersion in Medellín was security policy and addressing organized crime. The city, however, is also internationally known for its social urbanism interventions, and the field activities allowed participants to observe how these different dimensions of urban transformation coexist across the territory. In different comunas, participants encountered streets with regular movement, public squares and recreational areas, urban infrastructure, and public transportation reaching the city’s highest areas.

This transformation became even more visible at the conclusion of the immersion on Saturday (15), with a visit to Comuna 13. Historically marked by violent conflict, the area now presents a very different reality, with visible policing, urban infrastructure, and high levels of movement among residents and tourists. For participants, the visit brought to life one of the main issues discussed throughout the week: what changes in a territory when armed control no longer determines who can enter, move around, and provide services. The experience is particularly relevant to Rio de Janeiro, where restrictions on the movement of public officials, utility providers, and other external actors remain one of the main consequences of territorial control exercised by armed criminal groups.

By bringing together academic training, field activities, institutional visits, and direct contact with researchers, public officials, and public security professionals, the immersion marked an important stage of the Public Security Leadership Academy and contributed to the development of the projects that participants will present during the final stage of the program.