The 12 killings — and three other slayings this week that have been all but lost amid the carnage at the Navy Yard — pushed this year’s homicide count to 82, compared with 64 at this time in 2012. D.C. Police Chief Cathy L. Lanier added the Navy Yard slayings to the District’s crime statistics but added an asterisk marking them as an exceptional tragedy. The city’s homicide count jumped 28 percent.
As more cities across the country join the grim list of those that have experienced mass-casualty attacks, authorities are struggling with how to record them for statistical purposes and present them to the public in proper context.
In big cities and small towns alike, leaders often cite murder rates as a measure of safety in communities. But mass attacks don’t comfortably fit into categories designed for killings during holdups, drug deals or domestic fights.
When numerous people are fatally shot at movie theaters, in schools and in offices, it skews annual statistics, instantly turning what could have been a low-crime neighborhood into the statistically most dangerous. Some officials argue that the spikes artificially inflate violence and don’t accurately reflect crime trends. Some places keep such tragedies off their lists, often because federal authorities took over the investigation, or because they consider them acts of terror instead of crime.
Authorities in Aurora, Colo., held meetings filled with soul searching to come up with a way to record last year’s killings of 12 patrons at a downtown movie theater. On the police crime chart, they listed the total number of homicides at 29 — including those who were killed in the mass shooting — but also put a number 12 in parentheses next to the total. In the town’s annual report, police explained that the victims claimed by one gunman turned what would have been a 3.5 percent drop in violent crime into a 1.9 percent increase.
“We didn’t want our tragedy to be a reflection of our crime rate,” said Sgt. Cassidee Carlson, a spokeswoman for the Aurora Police Department. “It’s very clear that what happened is not typical. Obviously, it needed to be reflected. It happened. But we wanted to be smart about how we reflect what happens in our city.”
Police in the District, unlike in other cities, handle the investigations of all homicides, whether they happen on a city street or in a federal park. Authorities knew the Navy Yard shootings would alter the year’s statistical landscape on crime.
“We had the lowest number of homicides last year in 51 years,” said D.C. Mayor Vincent C. Gray (D). “Obviously now we’re not going to be able to make that this year unless some miracle happens.”