Acoustic sensors that alert police departments to gunshots have helped police in Washington, D.C., respond to thousands of shooting incidents, an investigation by the Washington Post revealed this week.
They have recorded about 39,000 shots since 2009, according to the Post, or 17 shootings daily.
The ShotSpotter Sensors, made by SST Inc., of Newark, Calif., identify gunshots and their locations, sending a signal to police and to ShotSpotter headquarters. The police can then dispatch officers to a precise location based on where the sensors heard the shots, company CEO Ralph Clark told ABC News today.
The sensors, developed in the 1990s, are now used across the United States., including Chicago, Atlantic City, N.J., Palm Beach, Fla., and Kansas City, Mo., according to the company, allowing police officials to respond more accurately to reports of shots and to collect data in order to analyze patterns of gun violence in certain areas of cities.
In Washington, the ShotSpotter was more accurate in distinguishing which loud noises were actually gunshots, as opposed to cars backfiring, construction noise or helicopters, former D.C. police chief Charles Ramsey told the paper.
The sensors also help inform police of an exact location where a shooter might be by using multiple sensors in the area to transmit data at once, according to the report.
More than 80 cities now use the technology, CEO Clark said. For most cities, the sensors feed information directly to the company's analysts, who in turn send detailed information to dispatchers. Because the sensors can pick up whether there are multiple shooters and whether an automatic wepaon is being used, the analysis is key to helping dispatchers plan how to get officers to the scene safely, Clark said.
The sensors were developed in the mid-1990s by Robert Showen, an engineer in California who was dismayed by gun crimes in his area, according to the company.
They were first implemented in D.C. as part of a federal grant in 2005, according to the Post.
"Wrapped in a weatherproof container roughly the size of a watermelon, each ShotSpotter sensor combines microphones, hardware, software and a clock linked to the Global Positioning System, which uses satellites and radio navigation to pinpoint precise times and locations," according to the report.
The systems cost anywhere from $55,000 to $70,000 per square mile, which can include about 15 to 20 sensors in that square mile, ShotSpotter's Clark said.
The Metropolitan Police declined to provide a comment to ABC News.