(Memphis) On the streets of Memphis, gangs and guns go hand in hand. Therefore, members of law enforcement can't fight one without fighting the other.
WREG got an inside look at how police are using the latest technology to track firearms used in violent crimes.
According to statistics from the Memphis Police Department, 110 of the 132 homicides for 2013 involve a firearm. Roughly a fourth are tagged as gang related.
If the latter number seems puzzling, considering Memphis' gang problem, it's because experts say it's not a true reflection of what they're dealing with.
For example, the Multi-Agency Gang Unit currently has 55 pending homicide cases involving gang members.
It's the same unit that prosecuted the case of Dexter Cox. He was convicted for killing three people, and has received multiple life sentences.
According to prosecutors, Cox was a gang member with a notorious love for guns.
However, because the murders had nothing to do with gangs, the case wasn't tagged as gang-related.
The Cox case also serves as an example of how technology plays a key role in investigations.
There was evidence scattered at each crime scene that ended up serving as pieces of a puzzle to connect the three murders.
Police collected shell casings and other gun evidence, then sent it to the Tennessee Bureau of Investigation Western Tennessee Crime Lab for ballistics testing.
It's where lab techs use sophisticated microscopes to look at markings on evidence.
They can determine how many guns were used in a crime, and match bullet fragments and shell casings to a gun.
Ray Lepone is the Chief Prosecutor for Shelby County's Multi-Agency Gang Unit.
He says, "If you can get a piece of evidence that is scientifically sound for instance like shell casings or obviously the murder weapon, now you are dealing with a piece of evidence that can't be manipulated."
Lepone served as the lead prosecutor in the Cox case where ballistics played a major roll.
In October 2007, the TBI matched cartridge casings from two, separate murders. The same .40-caliber gun was used in each.
Police had no suspects until three months later when the same gun was used to kill Lt. Ed Vidulich of the Memphis Police Department.
W.D. Merritt was the lead detective on the case.
"I got a call early that morning and my supervisor called me and said they had found Lt. Vidulich shot to death in his house."
Merritt said, "You could tell some things had been messed around, the house had been disturbed, then we found him there and found the shell casings."
From the beginning, there were rumors of extortion, stolen guns, and a mystery man named Tony Smith.
As Merritt and his team began to peel back the layers of this case, they stumbled upon a major break three days after Lt. Vidulich was killed.
An officer looking into Tony Smith learned about a teen being arrested for shooting a gun across the street from Frayser High School.
That teen was Dexter Cox.
"This officer was able to identify Dexter Cox as Tony Smith who was in the home of Ed Vidulich when he called to report the burglary," Lepone says.
Police also knew a gun was missing from Vidulich's house. Merritt then got the serial number from the gun Cox was arrested with.
"The serial number on that gun matched the box, the empty gun box that was inside it, Vidulich's house," Merritt added.
This was enough for police to bring Cox in for questioning.
Oddly enough, they picked him up at the Criminal Justice Center where he'd shown up for a hearing on that misdemeanor charge.
Merritt told WREG, "We knew we had some real good evidence at this point, but we still had to be able to put, to prove that Dexter pulled the trigger."
Cox gave multiple statements over the next two days and eventually confessed to killing Lt. Vidulich.
"When Dexter Cox is sitting across from the police and confessing to one murder, what he did not realize at the time was he was confessing to three," Lepone explains.
That's because what Cox didn't know at the time, is that police had already matched ballistics from Vidulich's case to the October murders.
Merritt says Cox eventually led them to the gun.
"Then we were able to actually find the murder weapon when Dexter told us where it was hidden."
While the confession sealed it, the ballistic evidence put all the pieces together.
"It's invaluable to have that technology to be able to do that in these cases," says Lepone.
According to law enforcement, it's actually rare for police to recover the murder weapon.
Guns change hands quickly and criminals know how to get rid of them, making the technology even more critical when the gun is found.