An armed robbery case caught on camera appeared to be heading for a dead-end in Wayne County.
So instead of DNA or fingerprints, detectives tried something that has never been used before in the United States.
Wayne County Sheriff Ric Wilson says three armed men robbed a liquor store near the Alabama state line on Jan.4, 2017.
“We had absolutely nothing -- we had no vehicle they were in, we had nothing to identify them with,” said Wilson. “It was a well-planned robbery. They were out in a minute and 38 seconds."
Investigators continued to pour over their only clue, the surveillance video.
Wilson says they decided to check surveillance video from a few weeks prior to the robbery to see if there were suspicious people that came in to "case the store out."
"Well, we saw two people who came in the day before," Wilson said. "We started watching the way one of them walked, he had a little bit of a distinct walk."
That "gait" got the attention of a forensics expert in Indiana.
“He said, 'if you have a known and an unknown, I can look at them and compare them,'" Wilson explained. "A few weeks later, he called us and said, 'I have confirmed, these two, the customer and the guy that robbed the store, they are the same people.'”
Through "forensic gait analysis" investigators charged 30-year-old Quinton Nance with aggravated robbery.
Wayne Co. Sheriff’s Office also arrested 29-year-old Cory Fuqua and 33-year-old Jesse Armstead.
District Attorney General Brent Cooper says this is another tool for law enforcement to help prosecute criminals.
“The one thing you're not going to be able to disguise is the way you walk,” said Cooper. “We were willing to use this case as a test to see if the courts in Tennessee would accept this kind of proof."
This is the first time in the United States that a grand jury indictment was secured strictly using gait forensic analysis.
But even if the courts had determined this evidence was not admissible, it was enough to make Nance confess to the crime.
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