The Great Minneapolis Crime Wave: Numbers don't lie, do they?

class=img_thumbleft>A few Fridays back, the Star Tribune ran an above-the-fold story about a supposed 35 percent jump in the violent crime rate in Minneapolis in 2005. As it turned out, that eye-popping number was based on flawed data submitted to the FBI by the Minneapolis Police Department. The actual increase, according to the MPD, was a more modest 15 percent. Still, 15 percent is pretty alarming. So, after the correction was duly noted, the editorial boards resumed their fretting, the bloggers continued to roar, and the politicians returned to their usual posturing. Everybody, it seemed, agreed on one point: Minneapolis is mired in a crime wave.

But what if that isn't the case? What if the reported "surge" in crime is mainly a function of statistical variation? That possibility should not be over-looked, says Candace Kruttschnitt, chair of the Department of Sociology at the University of Minnesota. "It may be premature to get all up and arms about Minneapolis. This could just be a short term fluctuation," Kruttschnitt offers.

Kruttschnitt acknowledges she could be wrong. But from a criminologist's perspective, she says, a one or two year spike in numbers doesn't establish a trend; she would like to see a five year pattern before drawing a definitive conclusion.

Even if there is an actual crime wave, Kruttschnitt cautions against the urge to embrace zero tolerance policing, tougher sentences and other harsh public policy remedies. In the course of the 1990s, she notes, crime rates plummeted across the U.S. and much of the western world. While some places where this occurred had indeed initiated get-tough-on-crime policies, she observes, many others did not. She cites the example of Canada, where crime trends there have long mirrored those in the U.S. despite the considerable differences in criminal justice approaches.

Kruttschnitt's contrarian views may not hold much appeal for some crime-weary Minneapolis denizens. But she is not alone in urging people to turn down the heat when discussing crime statistics. Steven Leavitt, the economist and Freakonomics author, argues that much recent reporting has grossly over-stated the significance of the national crime numbers (which, it should be noted, were considerably less dramatic than the Minneapolis figures).

Writes Leavitt: "So the actual increase in violent crime from 2004 to 2005: 2.5%. Given that violent crime has fallen 40-50% since its peak, this hardly seems like reason to panic. And I find it very interesting that none of the headlines I could find made any mention of the fact that property crime fell 1.6 percent. I guess after so many years of falling crime, more falling crime just isn't newsworthy."