When police slapped the cuffs on Donald Eugene Smith this month for the murder of a DeKalb County schoolteacher, the odds were about 10 billion to one that they had the right guy.
That is, until they learned he had an identical twin.
The improbable case hinged on a cigarette butt found under the driver's seat of Genai Coleman's car. A single mother of three, Coleman, 40, was waiting to pick up her teenage daughter near a transit station in Duluth on July 18, 2008, when someone fatally shot her during a carjacking.
Witnesses described the shooter as a black male wearing a white shirt with green sleeves and carrying a backpack. A man fitting that description was captured in surveillance video at an adjacent QuikTrip gas station. A similar-looking man was also seen in the vicinity of where the car was abandoned in Forest Park a few hours later.
The cigarette butt seemed to be the linchpin. Gwinnett police Detective Damien Cruz said that when a saliva sample from the cigarette was entered into the national DNA database of convicted felons, authorities discovered that it matched Donald Smith, who had a prior drug-related conviction. He was arrested Feb. 3 on murder charges.
But when confronted with the incriminating video footage in the interrogation room, Donald said it was his twin brother on the video, according to Cruz, who testified Friday at a probable cause hearing.
"He said, ‘Show that video to my sister and my parents, and they will also say the same thing,' " Cruz said.
Bradley Pearson, a former scientist at the state crime lab who has testified in over 100 cases about DNA analysis, said that in a typical case, the odds of two people sharing the same profile are at least 10 billion to 1. There are only about 6.8 billion people on the planet. However, two male identical twins would have the same DNA profile.
"You cannot tell the difference between which one is which," Pearson said.
Investigators took several days to track down Ronald Smith at his parents' home. The parents and sister both subsequently confirmed that Ronald, not Donald, was the man in the surveillance video.
Ronald was further incriminated when an analysis of his fingerprints matched those left by the suspect in Coleman's Dodge Intrepid. Cell phone records also showed that Ronald was in the area where Coleman's car was dumped shortly after the shooting.
When faced with the evidence, Ronald Smith admitted shooting Coleman with a .357 Magnum and stealing her car, police said. He was arrested for Coleman's murder on Feb. 6 and Donald was set free.
Detective Gilberto Lorenzo, who assisted with the investigation, said "I'm glad it turned out and the right person got arrested."
"Most people say, "It wasn't me' or they've got some other kind of excuse. This time it was true."
Ronald Smith is awaiting trial at the Gwinnett County jail without bond. The victim's sister, Camelia Coleman, said Ronald Smith is a "loose cannon" who doesn't deserve to be walking the streets.
"There's no reason for him to ever enjoy the freedoms we have," Coleman said.
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