In some cities there is - kind of. DC, for example, publishes all ShotSpotter events publicly and you can download all records of their events. You can notice

In some cities there is - kind of. DC, for example, publishes all ShotSpotter events publicly and you can download all records of their events. You can notice by plotting their events that there is a lot of extra "shots fired" on January first (probably from fireworks). If you knew of gunshots at a specific geographic coordinate you could confirm or deny with the DC data. I suppose you could also go to some specific spot in DC and fire a gun to see if they could detect it - but I don't recommend that. https://opendata.dc.gov/datasets/DCGIS::shot-spotter-gun-shots/about https://opendata.dc.gov/datasets/DCGIS::shot-spotter-gun-sho...