Violent crime in America has been falling for two decades. That's the good news. The bad news is, when crimes occur, they mostly go unpunished.

In fact, for most major crimes, police don't even make an arrest or identify a suspect. That's what police call "clearing" a crime; the "clearance rate" is the percentage of offenses cleared.

In 2013, the national clearance rate for homicide was 64 percent, and it's far lower for other violent offenses and property crimes.

University of Maryland criminologist Charles Wellford says police have shifted priorities over the decades.

"In the '60s and '70s, no one thought that the police should be held responsible for how much crime there was," Wellford says. Back then, he adds, police focused on calls for service and solving crimes.

In more recent years, he says, police have been pushed to focus more on prevention, which has taken precedence over solving crimes — especially non-violent offenses.

In short, the falling crime rate we've enjoyed may come at a cost: police indifference when you report your stereo was stolen.

The FBI collects clearance statistics for its annual "Uniform Crime Report," but it doesn't break those numbers down by jurisdiction. That makes it hard for people to compare local police departments' clearance rates, or track them over time.

So NPR asked the FBI for the local numbers, and the result is the tool above. Now you can look up the clearance rates of most local law enforcement agencies, for three years running.

A few things to keep in mind:

  • The quality of American crime statistics is notoriously uneven, and these are no exception. Sometimes cities fail to report, or their data are rejected because of errors. For instance, this database shows the New York Police Department clearing zero homicides in 2011 and 2012 — which was clearly not the case.
  • These data follow the standards of the FBI's Uniform Crime Report. One of the idiosyncrasies of UCR Summary data is that clearances are credited to the year in which the crime was cleared, not the year in which it was committed. As a result, it's sometimes possible for a city to clear more murders than were committed in a year, for a clearance rate above 100 percent.
  • Some cities will claim different clearance rates, based on another federal statistical standard known as the NIBRS. We decided to stick with the more widely-used UCR Summary standard, to allow people to compare like with like. ( Here is an explanation of the differences between UCR and NIBRS.)
  • We've left out clearance statistics for sexual assault, because experts in the field have advised us that reporting inconsistencies make those data too unreliable.

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