Chicago needs to get better at catching murderers.

Back in 1979, we reported that Chicago Police had solved 82 percent of all murders in the previous year — and we didn’t think that was good enough. In some years in the 1960s, the police solved murder cases at a rate of higher than 90 percent.

EDITORIAL

But high murder clearance rates are just a memory. Since Jan. 1 of this year, more than four out of every five murders in Chicago have gone unsolved. That’s a shockingly low number, perhaps even a historic low. On what grading curve is 20 percent anything but utter failure? Since 2006, the city’s murder clearance rate has dropped steadily, with just a couple of notable bumps up.

Fewer arrests mean more killers on the streets. More killers on the streets mean nobody is quite as safe. And when killers are not caught, others are less afraid to kill.

We can’t blame the soaring numbers of unsolved murders on restraints that supposedly have been put on police or declines in morale after such scandals as the 2014 Laquan McDonald case. The percentage of cleared murder cases has been declining for decades.

To turn the numbers around — to catch more murderers — Chicago above all needs more detectives. The city plans to bring the total number of detectives up to 1,200 from the 800-plus now on the job, but that will return the staffing level only to about what it was in 2008, when there were many fewer murders. Detectives still will have heavy caseloads.

Chicago also is investing in new technology. Computer algorithms predict where the next crime will occur. A gunfire detection system uses sensors to instantly inform the police when shots are fired. New squad car lights are designed to emphasize police presence in the neighborhoods. Cellphone apps give police information about shootings and other incidents in real time.

We understand the police in Chicago face serious challenges. Witnesses who fear retaliation by gang members are reluctant to talk. Residents don’t always trust police and want to cooperate. Compared with the past, more murders are caused by guns, which are harder killings to track.

But that doesn’t explain why Chicago does such a poor job of solving murders compared to other cities. Last year, Chicago Police reported solving 29 percent of murders, while New York police solved more than 80 percent — and the FBI puts the national average at just over 60 percent.

What’s Chicago’s excuse?

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