Mayor says study proves police respond faster without ShotSpotter. The study excluded gunfire calls. – CWB Chicago

Robert Vargas, a sociology professor who leads the UChicago Justice Project, acknowledged that before analyzing response times, his students removed all 911 calls involving shots fired from the city’s dataset. In other words, the study’s conclusions about faster response times, if accurate, did not include gunfire calls, the only type of emergency ShotSpotter was designed to address and the specific response times elected officials had been discussing.