Despite the scale of tragedy, these cases are often just as hard to solve as regular shootings.
Over the past seven days, America witnessed five mass shootings that left three dead and 19 injured. The attacks bring the US mass shooting body count so far this year to 106 dead and 372 injured. That means more people have died in American mass shootings in the last four and a half months than were killed (by most estimates) in Ukraine's brutal protests between fall 2013 and fall 2014.
Meanwhile, Europe suffered one mass shooting this week, albeit an especially bloody one. Early Sunday, a group of bikers and locals were hanging out in an abandoned brewery in the Russian town of Chelnokhovo, not far from Moscow, when some of the bikers reportedly insulted 27-year-old Ilya Aseyev. Taking offense, the man allegedly left and returned with a firearm at about 6 AM, killing five people. That assault brings Europe's mass shooting body count so far this year to 18 dead and 55 injured in 15 incidents.
The shooting in Chelnokhovo wasn't just deadlier than all of this week's American mass shootings combined—it was also the deadliest such attack in Europe in 2016. But while the attack was horrific, justice (dubious as that term may be in Russia) was swift; two female witnesses spared in the attack helped police identify and arrest Aseyev within the day. That makes for a stark contrast with the aftermath of many American mass shootings, where the authorities seem to have trouble identifying potential suspects, and all too often never make an arrest at all.
The United States has a notoriously high rate of unsolved homicides: 211,000 such cases accumulated between 1980 and 2015, with almost 5,000 more added annually. (Citing FBI statistics, NPR reported last year that about 64 percent of all homicide investigations nationwide go unresolved.) You might expect mass shooting cases, including those with no deaths, to be easier to crack given their visibility. But according to David L. Carter, a criminologist at Michigan State University and an expert on homicide clearance rates in America, it's not that simple. The method and scale of a violent crime doesn't necessarily determine how hard it is to solve; mass shootings are still prone to all of the complications that have stymied police investigations increasingly since the 1960s, when national clearance rates on homicide cases were more like 90 percent year on year.
A decline in certain types of crimes of passion has increased the relative rate of stranger-on-stranger (or at least seemingly random) attacks, which are harder to investigate. That's especially true if you can't track down a perpetrator via powder residue, shell casings, bullets, or other forensics. Tension between violence-prone communities and the police, the emergence of "no snitch" culture, and the fear of retaliatory attacks by the shooters can also hinder efforts to gather witness testimony. The result is pockets of virtual impunity with massive numbers of unsolved murders when compared to the rest of the country.
We can see many of these factors at play in America's mass shootings this past week. The first four incidents all basically line up with characteristics of "random" or "gang" violence. Last Friday at about 8:15 PM, one person was killed and four were wounded outside of a carwash in Detroit, Michigan. Then, around 9:10 PM, a street shooting in Montgomery, Alabama, injured four more. On Sunday morning, at about 2:30 AM, an altercation between two men in line for a food truck in Austin, Texas, left one of them dead and three women injured. And on Wednesday night at about 8 PM, another street shooting in Chicago, Illinois, wounded five more. Investigations in these cases have moved slowly, and may go nowhere given the context of the crimes.
That leaves one less opaque mass shooting on Wednesday night in Birmingham, Alabama. A man allegedly injured four of his children and killed their mother in her home—a case involving two parties who knew each other, as well as vocal witnesses. The tragedy was followed by the arrest of the suspect the morning after the shooting.
"There is a point when a community demands a response" to tricky but emotionally resonant shootings, Carter tells me—especially in the case of very public incidents with high body counts. The extra manpower and scrutiny in those cases may lead to higher clearance rates.
Conversely, some criminologists argue, investigatory failure just erodes trust in institutions, further limiting cops' ability to gather information.
Carter and company insist that this doesn't need to be a permanent predicament. Criminologists and ex-cops have suggested all manner of tweaks to policy and procedure, from changing protocol for investigations to better funding homicide units in poor communities (investigating murders is expensive) to overhauling the deployment and priorities of officers in murder hot spots. Whether any of these recommendations can increase the homicide clearance rate generally or the mass shooting clearance rate in particular remains to be see. But for now, America has to contend with the fact that there are large swaths of the country where you can unload a clip of ammunition from a moving car knowing there's a good chance you'll get away with it.
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