A Shot Spotter employee sits in the incident review center where data is analyzed. Shot Spotter uses technology to analyze the audio waveforms of sounds recorded across various U.S. cities.

There’s no real way for the human ear to determine the difference between a fireworks sound and a gunshot. And that means an increase in shots-fired calls to local law enforcement in the weeks around the Fourth of July holiday.

“We get people that call up and say, ‘Yeah, it’s a Glock 22,’” Sgt. Roy Hoskins with the St. Joseph Police Department said. “Well, there’s no way to possibly tell unless you’re standing next to that person what it is.

“They fool us sometimes,” he added. “Very hard to tell the difference, especially in town where they echo.”

According to Hoskins, police still treat any reported shots-fired call as if it is real until they can prove otherwise. He said the problem is there’s an increased risk for officers and the public when police respond to shots-fired calls.

“If it’s not a legitimate shots-fired call and we’re responding that way to fireworks, that puts us at risk and that puts the public at risk,” Hoskins said.

There is some technology, from a company called ShotSpotter, that claims to generally differentiate between the sound of fireworks and the sound of gunshots. The company says its technology can triangulate the location of gunfire within 60 seconds using sensors placed throughout a city. If it’s not clear what produced a sound, an employee from ShotSpotter analyzes the data.

“This process can involve not only listening to sound recordings but also looking at the waveform images, which show the visual representation of an audio signal. Gunshot waveforms tend to look distinct, resembling pine trees tipped on their sides,” Ralph Clark, CEO of ShotSpotter, said in a release.

According to the company, the technology is in place in Kansas City and more than 100 other cities. But St. Joseph has to go old school, relying on callers to make reports.

“Some cities have the triangulation devices where they can hone in on a specific area for gunshots, but we don’t have that technology available,” Hoskins said. “So what we rely on is if we have multiple calls say, ‘East of this location I heard a gunshot’ and someone else calls ‘South of this location I heard a gunshot’ we can get some kind of bracket set up.

“If we get any indications it’s a shots-fired call, we’ll look for shell casings, damage, victims and things like that,” Hoskins said. “You get close to Independence Day and they (shots-fired calls) go up exponentially.”

Hoskins said the police department isn’t trying to ruin anyone’s holiday, but they are required to enforce the law when called to do so. City ordinance prevents users from lighting off any fireworks that aren’t “safe and sane,” he said. That includes fireworks that shoot more than 6 feet off the ground.

“Within our city we’re pretty restrictive in what can be shot legally,” Hoskins said. “It’s things that don’t shoot in the air and things that don’t go bang.”

Hoskins said police can confiscate illicit fireworks and arrest those who continue to use them.

Matt Hoffmann can be reached


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