In 2017, homicides related to organized crime and gangs represented 64 percent of all homicides in Latin America whose cause was known. Gang-related violence and crime are top concerns among citizens throughout the region. Yet in Latin American cities where gangs control territory in low- and middle-income neighborhoods, policymakers face a dilemma: policies that aim to combat gangs may actually increase violence instead.
The city of Medellín, Colombia, illustrates this dilemma. During the mid-2000s, the international press was abuzz with stories about the “Medellín miracle,” a dramatic decline in homicides coinciding with pragmatic city leadership and the demobilization of paramilitary groups. But what is less well-known is that one of the most powerful drug traffickers in Colombia’s history, Diego Murillo Bejarano—better known by his alias, Don Berna—had consolidated near-monopolistic control over Medellín’s street gangs during this same period, along with the organized crime structures above them. He exercised his hegemony to manage gang conflicts and keep violence low. His surprise extradition to the United States in May 2008 created a power vacuum in the city’s criminal economy, and an internecine war for control saw homicide rates in the city double before organized-crime governance structures finally reconsolidated and violence returned to pre-extradition levels.
Studies of gang violence traditionally measure costs in terms of human lives and the strength of the rule of law. However, the consequences of gang violence likely have wide-ranging economic effects, especially on the development of young people. In Medellín, the paths many students follow to school put them at risk when they cross invisible gang boundaries. Gang violence and crime may cause the quality of schools to drop due to teacher turnover in conflict areas, inflict psychological trauma on students exposed to violence, or alter students’ perceptions of the value of education.
Our research estimates the impact of Don Berna’s extradition on homicides in Medellín. It uses these findings to estimate the impact of homicides on local students’ test scores. Our findings suggest that Don Berna’s extradition caused an average of 1.2 more homicides within 250 meters of a school each year from 2009 to 2013. Further analysis suggests that each additional homicide within 250 meters of a school led to a 1.1 percent decline in math test scores, equivalent to 0.05 standard deviations.
These effects were felt differently among students of various backgrounds. Homicides caused average test scores to fall the most for students from higher-income households and those at the upper end of the test score distribution. For males, particularly males from lower-income households, exposure to homicides led to higher dropout rates. This effect on dropout explains why the test scores of poorer students are less affected—the worst-performing students from poorer households dropped out as homicide exposure increased, so they did not take the test.
Our results also show that the effects were more significant for schools with the most exposure to homicides. For example, the effect of going from eight to nine homicides was much larger than going from two to three homicides. Additionally, the effect of a homicide that occurred farther from a school was smaller than the effect of a homicide that occurred closer to a school.
Additionally, our research investigates why homicides affected students’ test scores. Homicides increased the turnover rate for teachers with the highest qualifications. Moreover, the effect of homicides on test scores was approximately the same regardless of how soon it occurred before the exam date; this suggests that reasons related to long-term learning disruptions (e.g., teacher turnover, student absences, and school closures) more plausibly explain the effect on test scores than reasons related to short-term disruptions, such as acute psychological distress.
Our research provides evidence for the unintended consequences of a sudden change in criminal governance—the extradition of a major kingpin—on homicides and test scores. While we cannot conclude that every extradition of a narco kingpin or gang leader will increase violence, our results do suggest that targeting kingpins of highly consolidated and violent criminal organizations is a risky strategy that could increase violence between competing criminal factions. This echoes findings from related research in Mexico showing that homicides increased following kingpin arrests. Our research also shows that the consequences of extradition reach beyond the crime-involved individuals most often targeted by this violence, creating disruptions for schools in gang-controlled neighborhoods. This fits into a recent but growing body of research documenting the effects of exposure to violent conflict on education in various countries.
