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They found that the median response time from alert to arrival was 5.5 minutes, a decline of 1.2 minutes in the target area compared with the rest of the city. Alerts also more than doubled the gunshot notifications that police received. The 73 confirmed shootings that police knew about only through alerts led to 7 arrests. Only 9% of alerts without a 911 call were confirmed as shootings. The evaluators found no evidence that investigations of 911-reported shootings became more productive, and they could not determine an effect on gunshot injuries. One author disclosed that SoundThinking paid his travel to a January 2024 speech.","category":"aggregate result","unexpected":false,"purpose":"SoundThinking built ShotSpotter to detect gunfire with acoustic sensors and alert police to its location. 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