The most recent ranking of the world’s most violent cities by the Mexican research group Security, Justice, and Peace again drew attention to Latin America, which was home to 42 of the 50 cities on the list.
Latin America is indeed the most violent region, accounting for about 8% of the global population but tallying roughly one-third of the world’s intentional homicides.
While homicide is not the only kind of violent crime, it is generally considered the best measure of it.
“Of all the different types of crime, homicide is probably the easiest to track because there’s nothing more biologically evident than a dead body,” Robert Muggah, the research director at Brazil’s Igarapé Institute and an expert on crime and crime prevention, told Business Insider.
In most places, there are also legal procedures that authorities are supposed to follow when dealing with homicides.
“So unlike, say, assault or robbery or sexual violence or domestic abuse, homicide is one of those variables that across time and space is relatively straightforward to capture,” Muggah said, adding that researchers can draw on a panoply of sources — law enforcement, public-health agencies, nongovernmental groups, the press, and the public — to tabulate and track homicides over time.
But, as Latin America illustrates, there are a number of recurrent challenges that arise when collecting homicide data that complicate efforts to make comparisons and compile rankings.