(NewsNation) — It’s called ShotSpotter, and that’s exactly what it’s designed to do: detect the location of gunshots fired in real time.

The technology is being used by police departments nationwide to rapidly deploy officers wherever shots are fired when every second counts.

But are there flaws in the system? Critics question if ShotSpotter is doing more harm than good.

When shots ring out, it’s a race for authorities to get to the location in time. Those precious seconds and minutes could help save lives, stop a crime in progress, or catch a criminal.

But what if no one calls 911, or the call comes too late?

According to ShotSpotter, that’s when they step in.

ShotSpotter is a gunshot detection system used in roughly 140 cities nationwide to pinpoint gunfire in real time, allowing police to quickly respond to the scene of a crime.

It works by using sensors strategically placed on top of buildings or lamposts that are sensitive to loud impulsive sounds, like pops and booms that could be gunfire.

ShotSpotter typically deploys 20 to 25 sensors per square mile to alert local police to gunfire moments after it happens, allowing police to be dispatched within 60 seconds.

“It’s proven to be highly effective,” said ShotSpotter CEO Ralph Clark. “We start with a contractual guarantee of 90%. Although we know we’re operating at 97% accuracy, based on the cumulative feedback we have from over 140 agencies where we’re currently deployed.”

But can ShotSpotter backfire?

According to a study by the MacArthur Justice Center at Northwestern University, over a 21-month period in Chicago, 89% of ShotSpotter alerts turned up no gun-related crime.

A Chicago inspector general report found similar results, reporting that of 42,000 ShotSpotter calls police responded to, only 9% included a gun-related crime.

“There’s no such thing as a perfect technology,” Clark said. “I think when you compare it to the thing that we’re addressing, which is 80 to 90% of criminal gunfire going unreported by traditional 911. It’s a very effective solution. “

But some cities disagree. Dayton, Ohio, San Antonio, Texas, and Charlotte, North Carolina, all questioned the effectiveness of the technology and its usefulness before shooting down their contracts.

Activists in big cities such as New York, Houston and Chicago have urged city officials to cancel millions of dollars in ShotSpotter contracts, citing poor results, surveillance issues and danger.

“Nine times out of 10, police go out in response to a ShotSpotter alert, and they don’t find any corroboration of gunfire,” said Jonathan Manes, MacArthur Justice Center attorney. “They don’t find shooting; they don’t find witnesses. They don’t find somebody with a gun.”

In Chicago, a federal lawsuit to end the use of ShotSpotter alleges the Chicago Police Department (CPD) misused the technology, which led to the wrongful yearlong incarceration of a grandfather charged with killing his neighbor. The system is also being blamed for capturing the gunshots that led CPD to the location where a 13-year-old boy was ultimately shot and killed by Chicago police.

It makes people less safe because it brings aggravated police in this heightened state of alert into already overpoliced communities,” said activist Grante Kim of MPower Change.

But many police departments tout the technology, believing the good outweighs any flaws in the system, and they’ve even expanded it.

“It’s made the response time quicker because we know exactly where to go,” said New Haven Police Chief Karl Jacobson. “We’ve been able to solve more cases.”

Jacobson said he thinks the technology has had a positive effect.

But it’s only a piece of the puzzle,” he said. “It needs to be worked, along with a lot of other technology-type things. And, you know, good old police work.”

ShotSpotter’s CEO said while the company’s technology is not the singular reason for the prevention and reduction of gun violence, it is part of an overall strategy that can help put a dent in it, and he believes it’s a game changer.