Colombia’s Data-Driven Fight Against Crime


One Monday in 1988, El Mundo newspaper of Medellín, Colombia, reported, as it did every Monday, on the violent deaths in the city of two million people over the weekend. An article giving an hour-by-hour description of the deaths from Saturday night to Sunday night was remarkable for, among other things, the journalist’s skill in finding different ways to report a murder. “Someone took the life of Luís Alberto López at knife point … Luís Alberto Patiño ceased to exist with a bullet in his head … Mario Restrepo turned up dead … An unidentified person killed Néstor Alvarez with three shots.” In reporting 27 different murders, the author repeated his phrasing only once.

….What Guerrero did to make Cali safer was remarkable because it worked, and because of the novelty of his strategy. Before becoming mayor, Guerrero was not a politician, but a Harvard-trained epidemiologist who was president of the Universidad del Valle in Cali. He set out to prevent murder the way a doctor prevents disease. What public health workers are doing now to stop the spread of Ebola, Guerrero did in Cali to stop the spread of violence.

Although his ideas have now been used in dozens of cities throughout Latin America, they are worth revisiting because they are not employed in the places that need them most. The most violent places in Latin America are Honduras, El Salvador and Guatemala — indeed, they are among the most violent countries in the world not at war. The wave of youth migration to the United States is from these countries, and the refugees are largely fleeing violence.

One small municipality in El Salvador, Santa Tecla, has employed Cali’s strategies since about 10 years ago, and the homicide rate has dropped there. But Santa Tecla is an anomaly. Most of the region’s cities have not tried to do what Guerrero did — and they are failing to protect their citizens….

Guerrero went on to spread his ideas. Working with the Pan-American Health Organization and the Inter-American Development Bank, he took his epidemiological methods to 18 other countries.

“The approach was very low-cost and pragmatic,” said Joan Serra Hoffman, a senior specialist in crime and violence prevention in Latin America and the Caribbean at the World Bank. “You could see it was conceived by someone who was an academic and a policy maker. It can be fully operational for between $50,000 and $80,000.”…