Last summer a gunshot detection system was installed in Harrisburg's South Allison Hill neighborhood.  According to Harrisburg Police and the District Attorney's office, the sensors are making a significant difference in the fight against crime. Allison Hill resident Melissa Spencer told abc27 News she and her daughter feel safer now.  One of the big reasons why is the gunshot sensors.  "I think it's working," she said.  "I think there's a lot less violence."

The sensors seem to be everywhere.  Sixty-five of them were mounted on poles in a ten block area of South Allison Hill.  When a gunshot is fired, the sensors pinpoint the exact location within seconds.  Police don't have to wait for someone to call 911.
 
"You can catch people fleeing the area," said Police Chief Charles Kellar. "Sometimes they leave in vehicles.  You see somebody speeding away. In cases where somebody is shot you can get medical attention there quicker."

Chief Kellar thinks the system is well worth its $130,000 price tag.  He said the sensors made 97 detections in the first six months of operation.  But 80 of those detections were fireworks on the Fourth of July, leaving 17 detections of possible gunshots.

Kellar said in three of those cases someone was wounded.  In one, he believes a life was saved.

"It was about three o'clock in the morning where we did not get a call from a citizen," he said, "and had it not been for that system, we'd have never found that individual in time because he was pretty much incapacitated, most likely he would have bled to death."

When the system was turned on back in July, Dauphin County District Attorney Ed Marsico called the detectors effective crime deterrents.  The numbers aren't in yet, but the D.A.'s Office reports gun violence in Allison Hill has definitely dropped off. 

Has it risen though in other neighborhoods as criminals move into areas that don't have sensors?  It's too early to tell, according to the D.A.'s Criminal Justice Administrator Stephen Libhart. "I think that's probably an unfortunate by-product of it," he said, "but the deterrent factor alone is well worth it."

Libhart does say there has been an unforeseen benefit for prosecutors.  In at least two current cases, the sensors provided important evidence.

"The people offered one version of events and the secure system indicated there was probably another version that was closer to the truth," said Libhart.  "That has kind of helped investigations move along a little more quickly because we have direct evidence to refute what's being given in an interview."

Kellar would like to expand the system in Allison Hill and possibly add some cameras.  The system was purchased with government grants. The District Attorney's Office would have to secure more funding for an expansion to occur.