ShotSpotter is an Acoustic Gunshot Detection System (AGDS) used by law enforcement to detect and report the location of gun fire. These microphone and acoustic sensors are generally placed on utility poles and buildings, where they register and record a specific “acoustic signature” whenever a short, explosive, and loud sound is detected. ShotSpotter installs 20-25 audio detectors per square mile at a cost of $65,000 to $90,000. ShotSpotter is used in more than 130 U.S. cities and towns.
ShotSpotter poses significant Fourth Amendment, privacy, and equity issues. In the course of monitoring for gunshot-like sounds, ShotSpotter sensors continuously record audio, usually in high-minority neighborhoods. Without a warrant or any individualized probable cause, their sensors inevitably surveil many innocent people going about their daily activities. Despite its ubiquity, ShotSpotter doesn’t work. Millions of dollars of public funds are invested into technology that does not fulfill its stated purpose, which is to deter violent gun crime and improve police response to crime.
At Restore the Fourth, we work to pass surveillance ordinances across the country. ShotSpotter poses a major threat to our right to privacy. They erode our reasonable expectation to privacy, consume public funds at a rapid rate, and disproportionately impact those most vulnerable to police violence: BIPOC communities. We prepared this issue brief detailing the major privacy violations committed by ShotSpotter. It is the first analysis that attempts to quantify the cost of the police time wasted by ShotSpotter’s inaccuracy and faultiness. You can read this brief on our issues page here.