Cape police: ShotSpotter worked well around July 4

Cape Girardeau police officials say their gunshot detection technology worked well over the Fourth of July holiday.

The technology detects the sounds of gunshots in neighborhoods, with the promise it can differentiate gunfire from fireworks.

The technology is designed to alert law enforcement to gunfire and provide locations of the gunshots.

Cape Girardeau Police Department public information officer Bobby Newton said between July 1 and 6, the ShotSpotter technology recorded 15 incidents, four of which were categorized as fireworks. The police department recovered 16 bullet casings.

"Overall, the ShotSpotter technology worked well with our patrol in order to distinguish fireworks vs. gunfire and the location of the incident," Newton said.

No arrests were made over the holiday period.

The ShotSpotter system, created by a company now called SoundThinking, includes the placing of a large number of recording sensors throughout a city. According to previous reports, the sensors have been installed over a 1.2-square-mile area in Cape Girardeau, an area that has not been disclosed publicly. The sensors triangulate the location of the source of the gunshot within a few meters. The system is set up so the police are not alerted when a firework pops or a car backfires. The New York Times reported that the technology differentiates the sounds by listening to the cadence of the sounds as well as decibel levels, though some fireworks and some firearms can overlap in their decibel range.

ShotSpotter was installed in Cape Girardeau in May 2022.

To date, eight arrests have been made and seven firearms recovered in Cape Girardeau solely because of the technology, even when no city residents made a call to the department reporting gunshots. In fact, 67% of the ShotSpotter reports were not reported to the department by people.

A greater chance of arrests exists, however, when people are involved in gunshot calls to the police. Twenty-one arrests were made and 17 guns were recovered when ShotSpotter was aided by witnesses.

Overall, since the introduction of the technology, 323 incidents have been tallied, which is a little less than one per day. ShotSpotter has captured 1,187 shots fired since its installation, with 501 casings recovered. Of those shots reported by the technology, six victims were hit, while 22 buildings and 14 vehicles were struck by bullets.

Many have questioned the technology's accuracy and whether it acts to deter gun violence. The technology has not been widely studied by neutral third parties. The company relies heavily on anecdotal evidence and word of mouth to market its product. The company and law enforcement partners, citing confidential and proprietary data exemptions, have resisted efforts to analyze its methods, technology and data, according to Forbes. More than 100 jurisdictions are using the technology in the U.S. today. Critics have said that even though officers respond to more illegal gunfire, the shooter is still rarely caught.

Some defense attorneys have raised concerns relating to the Fourth Amendment of the U.S. Constitution. They argue that more transparency about the accuracy of the system is needed to determine whether a ShotSpotter alert is enough to detain someone for a crime if they're found near the coordinates of an alert.

In Cape Girardeau, in a little more than a year, the technology has played a role in 21 arrests out of 323 incidents, a rate of about 6.5%. The rate of arrests with no witness involvement is about 2.4%.

Cape Girardeau Police Department issued a news release ahead of the holiday weekend regarding ShotSpotter detection as a way to deter celebratory gunfire that "often has tragic results" according to that release. The department stated officers would respond to all ShotSpotter activations.