LOUISVILLE, Ky. (WHAS11) -- LOUISVILLE, Ky. (WHAS11) -- Before the bright lights start flashing and the yellow caution tape gets set up, there's the dispatch directing officers to a scene. It used to be 911 phone calls that would alert police officers to emergency situations, but for the last few months, Metro Police officers have been getting some extra help.

"It's a tool in the bag," Lt. James Cirillo said. "It has led to a few arrests that we may not have made had we not had Shot Spotter."

It has only been four months since LMPD started using Shot Spotter, a $1.3 million program that places microphones in areas of historically higher crime rates that detect gunshots and pinpoint their locations. According to Cirillo, the Shot Spotter program covers a total of six square miles through Louisville.

"It takes about 120 decibels to activate one of the Shot Spotter microphones," Cirillo said.

After a sound is detected and identified by a computer as a gunshot, a team of Shot Spotter Technology technicians listens to the sound to confirm the computer's determination. If the technicians confirm that the sound is indeed a gunshot, the information is sent to dispatch.

"A lot of times, an officer is already heading to the area where the shots have been detected before we're getting those first calls that somebody's been shot or injured," Cirillo said.

Cirillo, LMPD's technology services lieutenant, said Shot Spotter can save officers up to one and a half minutes - time that could be the difference between life and death.

"Every second counts," he said. "So, if you're getting a 30-second jump on a call like that, I think you're getting help to that injured person faster."

According to Cirillo, Shot Spotter has also helped detect situations that would otherwise not have been reported.

"About 86 percent of our Shot Spotter activation since we went live are strictly just a Shot Spotter activation, no call for service," he said.

LMPD admits Shot Spotter by itself is not the answer towards solving violent crime in the metro area, but it is an important piece to the puzzle, especially when coupled with good police work and contributions from the community.

Since June, Cirillo said Shot Spotter has reported more than 1,000 activations, most of which were confirmed as gunshots.

According to Cirillo, LMPD will continue to evaluate Shot Spotter's effectiveness during its three-year contract. If the department deems it effective, LMPD will likely continue using Shot Spotter, and could even expand its coverage.