Why fewer murder cases get solved
Police are working to reverse a downward trend, but budget cuts ahead may make the job harder.
On an autumn Thursday, shortly after 1 p.m., a postal worker in Virginia Beach, Va., found Samuel Baruch on the floor next to the safe in his office. He had been fatally shot during an apparent robbery.Skip to next paragraph
Subscribe Today to the Monitor
The brazen killing in 1991 was emblematic of a nationwide surge in violent crime that unleashed a wave of campaigns to clean up city streets. But 17 years later, six local homicides from that year, including Mr. Baruch's, remain unsolved.
For decades, the share of homicides that police solve has steadily declined – from over 90 percent in the 1960s to about 65 percent today. The trend defies advances in forensic technology and a federal initiative that has deployed more than 100,000 new cops since the early '90s.
Most surprising, it's persisted even as murders committed in the US have plunged. The national murder rate fell 40 percent between 1991 and 2007, but in a few large cities only about 1 in 3 murders got solved last year. With the economic downturn, expectations are fading that police departments can improve their record by devoting more manpower to tracing killers. Nearly 40 percent of law-enforcement agencies have already cut their budgets, according to a July survey by the Police Executive Research Forum.
"What's going to happen is that you're going to have fewer police trying to solve just as much crime," says criminologist Jay Albanes of Virginia Commonwealth University in Richmond. "If that's the scenario, you can't just continue doing what you're doing now, or you'll continue to slowly slide backwards."
A common explanation for the slide in US closure rates is the gradual but steady shift in the profile of the typical murder. A few decades ago, a majority of homicides involved acquaintances and were not premeditated. Today, most involve strangers and often accompany other criminal activity. Such cases generally present fewer and more-reluctant witnesses.
About three-quarters of murders in Boston are tied to gang members, says Thomas Lee, deputy superintendent of the police department's criminal investigations division and forensics section. That drives down the homicide closure rate, he says, which stood at 36 percent in 2007.
"It's frustrating for us a lot of times," Superintendent Lee says. "Sometimes getting the public on board is our toughest challenge."
Some researchers argue that police work itself is what most influences the closure rate. Boosting the number of homicide detectives assigned to a case from one to four more than tripled the probability of solving it, says Charles Wellford, a University of Maryland criminologist who cowrote a landmark 1999 study on the issue. Decreasing their initial response time also had a large positive effect, he found.
"Only partly is the clearance [rate] driven by the nature of the crime," he says. "If you're looking for reasons [for whether cases get solved], you have to spend some time looking at how police have organized and conducted their investigations."