Editorial: Crime-fighting and humility best go hand in hand

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Updated: March 2, 2012 8:16AM

Crimes rates are like the weather. You have to study the ups and down over a long time, at least several years, before you can claim any kind of an important trend.

Veteran police officers know this. That’s why they usually are slow to credit good police work for any short-term drop in crime rates, especially murder. If they grab the credit now, they know, they’ll have to accept the blame later when crime rates climb back up, which inevitably they will, at least in the short run.

Mayor Rahm Emanuel is new to this game. Maybe that’s why his administration, in a real rookie mistake, made a fuss less than two weeks ago when there were no shootings or murders in the city for a full 24 hours.

“This is clearly the result of the tremendous police work of the men and women of the Chicago Police Department,” Emanuel’s new police superintendent, Garry McCarthy, said then.

Emanuel got great press for that one.

But now the tide has turned. According to the latest figures, Chicago in January (even given that one quiet day) actually suffered a 53.8 percent jump in murders, with 40 as of midday Monday compared to 26 for the same period last year.

And are the cops taking the blame? Not that we can see.

Nor do we think they should.

Our guess is that the jump in murders had more to do with the unseasonably warm weather last month, encouraging more goofs with guns to get outdoors, than with anything the police did or did not do.

Emanuel and McCarthy are understandably eager to seize on any evidence that their new police strategies are working, especially given criticism from many rank-and-file officers that the Police Department is undermanned.

But they surely know what really drives crime — social woes such as unemployment, family dysfunction, drugs, poor schools and the like — and they surely know the limits of what even the best police force can do.

A little less bragging would be in order.