What does the science say about ShotSpotter?

Our Take

Credit to the Chicago Justice Project for sitting down with Dr. Eric Piza and walking through what may be the first independent, peer-reviewed look at ShotSpotter's real-world impact. The headline finding is blunt: faster response times, sure, but no measurable drop in gun crime and no meaningful bump in arrests or convictions. That's a big deal, because cities have spent years and tens of millions of dollars justifying these systems with vague promises of "public safety," not actual outcomes data.

This matters beyond ShotSpotter itself. It's the same playbook used to sell automated license plate readers like Flock Safety's camera network — install first, ask for evidence later. When the people footing the bill and living under the sensors finally get independent researchers to check the math, the results rarely match the marketing. If acoustic gunshot detection can't show it reduces crime after years of deployment, that should make every city council pause before rubber-stamping the next surveillance contract, ALPR or otherwise.

We keep track of where these systems are actually going up and who's paying for them. Check our map to see what's been deployed near you, and if your local government is about to approve new surveillance tech without proof it works, head to our take-action page to find out how to push back before the contract is signed.