How a Sophisticated Gunshot-Locating Device Kept Giving Police False Alarms

Last year, New Haven and Hartford cops were seriously pissed off at all the time they were wasting chasing down false reports from their supposedly high-tech "ShotSpotter" gunshot locating systems. They were rushing out to find the "gunshots" were actually from jackhammers or loose manhole covers hit by cars.

Even worse was the case in New Haven's tough Newhallville neighborhood where somebody fired off 10 rounds from a .45 caliber pistol — shots that ShotSpotter's acoustical sensors apparently failed to pick up. By some reports, more than 95 percent of Hartford's ShotSpotter alerts were false alarms.

Today, police in both cities are saying most of the problems have been fixed and that ShotSpotter is now a lot closer to what it's supposed to be: a marvelous technological tool to help law enforcement quickly pinpoint and react to gunshots in high crime areas.

"We believe it to be about 80 percent accurate now," says Hartford Police Lt. Brian Foley.

In New Haven, Sgt. Max Joyner estimates that the fixes now in place "have cut down by about 90 percent on the false hits."

ShotSpotter was purchased by both departments more than a year ago in an effort to combat violent urban gun crime.

The system uses audio sensors placed on telephone poles and buildings at key points in an area. When a loud noise happens, the various sensors triangulate the location of the sound, and the recording of the noise and the location are automatically sent into a central location.

In theory, that means police can be dispatched to the location almost immediately, giving them a far better chance to stop any further violence, help any victims, or catch the shooter.

But all those false reports and failure to pick up actual gunshots raised so many questions that New Haven Police Chief Dean Esserman told the New Haven Register last year that either the problems were going to be solved or the system shut down.

"We need to gain confidence in ShotSpotter," he said.

Foley says Hartford officials called in experts from ShotSpotter's California headquarters and worked with them "to iron out some of the technical glitches" that were screwing up the system. New Haven did the same.

The solution, according to officers in both departments, involved even more high-speed technology and expertise.

Under the original system, the initial sound recordings and locations were being sent through local computer systems to local police personnel and dispatchers in both cities. Those people would then have to decide if the sound was actually a gunshot or something else, and they apparently weren't getting those calls right often enough.

The solution, police officials say, was to re-route those initial signals directly to ShotSpotter's more sophisticated server computers and highly trained experts at the company's California operations center.

"They have much more sophisticated equipment," explains New Haven Police spokesman David Hartman.

Foley says the alleged gunshot sound would then be reviewed by ShotSpotter's in-house experts, and a report immediately sent back to the local police dispatcher. If the sound was estimated to be from a gun, the report would indicate whether it was a single shot or multiple shots or only a possible gunshot.

The whole process of sending the signal to California, having it reviewed and a report sent back to New Haven or Hartford dispatchers happens "within a minute" or at most 90 seconds, according to Foley and Joyner.

Both cities are now operating ShotSpotter systems under one-year contracts with the company, officials said.

New Haven first installed the system in 2008 using a $500,000 federal grant that covered most of the initial cost. Joyner says the new contract calls for the city to pay about $49,000 annually for the cost of upkeep and services.

Foley says Hartford has thus far paid about $75,000 on its ShotSpotter system and will have to pony up another $75,000 at the end of the contract year in January.

He says the sound detection program can sometimes locate the point of the gunfire with amazing accuracy. "We've used the mapping software to find shell casings," Foley says.

Connecticut's largest city doesn't yet have a ShotSpotter system, largely because of budget constraints, says Bridgeport Police spokesman Bill Kaempffer. But he adds that police there would definitely like to get it.

"The chief has it on his wish list," says Kaempffer.

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