That data have been much-anticipated, because the lack of data has long been a critique of the gunshot detection technology . The Chicago Office of Inspector General previously found that the majority of ShotSpotter alerts fail to turn up any evidence of a crime.
The data, which show 29,829 ShotSpotter alerts from the beginning of 2024 through Aug. 31, seem to show more evidence of crimes connected to ShotSpotter alerts. Shell casings were recovered in the majority of responses to those alerts, and 470 weapons were recovered.
ShotSpotter alerts also produced response times that were on average about three minutes faster than 911 calls alone—with 11.9 minutes for ShotSpotter alerts alone, and 14.3 minutes for just 911 calls.
But of the 143 victims who were rendered aid as a result of a ShotSpotter alert, only seven of those victims got help when there was no corresponding 911 call. In other words, police were also alerted to the majority of the cases that ended up involving rendering aid by people calling 911.
"That's an area we would definitely like to explore with CPD to better understand," said Gary Bunyard, vice president of corporate development for ShotSpotter parent company SoundThinking.
Bunyard was present at the meeting Monday, and said the company questions the statistic about ShotSpotter and victims who were given aid—because in other markets where ShotSpotter technology is used, the percentage of "victims helped without a corresponding 911 call" is much higher.
The vast majority of the City Council members who spoke Monday were against the contract ending.
"I have here signatures collected from residents in the police District Number 8 supporting ShotSpotter—over 1,500 signatures," Ald. Silvana Tabares (23rd) said as she held several sheets of paper in hand.
"We know that the doomsday is September 22. That's what I'll call it," said Ald. Monique Scott (24th). "We're basically going to play Russian roulette without constituents' lives."
Ald. Ray Lopez (15th) said allowing ShotSpotter to be removed might lead to further removal of law enforcement technology.
"If we allow ourselves to go down this road of removing technology, which technology is next?" he said. "Are we going to take out license plate readers next?"
"What are we talking about to replace ShotSpotter?" said Ald. Matt O'Shea (19th). "What investments in technology are we talking about to make these communities safer?"
Former Chicago Police Supt. Eddie Johnson , who led the CPD when the technology was first installed, attended the hearing and said the latest data prove why the city should keep the system.
"I still love this city and I love CPD, and I live here, and we have the obligation to do the right thing," former Supt. Johnson said. "It would be a totally different conversation if we had something to replace that technology—but the fact of it is, we don't."
Johnson warned that he believes the consequences of no more ShotSpotter could be serious.
"Homicide numbers will probably go up," he said, "because those victims that we responded to quickly before, we won't be able to get to."
But Ald. Byron Sigcho-Lopez (25th) said the city should focus on other social priorities. He and other critics feel that the funds allotted to the current $49 million ShotSpotter contract could be better spent.
"I think I urge my colleagues to look at ways to spend those $30 million that look into preventing violence; investing in young people," Sigcho-Lopez said.
Sigcho-Lopez was one of the few critics of the technology who spoke at the hearing Monday.
No votes were taken Monday. But if nothing is done before Sept. 22, the company will start the process of removing the roughly 2,000 sensors installed across the city.
There is no fee for removing the sensors. But if the city later decides to reinstall them, it will be costly.
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