Devonia Inman, at age 20 when first arrested, and today after serving nearly 18 years in prison for a murder he may not have committed.

From the moment he was arrested for murder, Devonia Inman said police had the wrong man. It would take more than a decade behind bars and new DNA testing before he thought he could prove it. But now, Georgia's justice system won't give him that chance. "What do I got to do when we've got DNA evidence that proves I'm not the person who committed this crime?" he asked from inside a small cage at the Georgia State Prison in Reidsville. His lawyers believe the scientific evidence proves another man fatally shot Taco Bell manager Donna Brown in a late night robbery. But in Georgia, DNA isn't always enough for a new trial. In 2014, the original trial judge in Cook County denied Inman’s request for a new trial despite DNA evidence recovered from a ski mask inside the victim’s car implicating another man.

"Imagine the crushing blow when the judge says, you know what, DNA doesn't matter." -Jessie Gabel Cino, an associate dean at Georgia State University's law school, who is trying to help free Inman.

Cino meets with Devonia Inman inside Georgia State Prison.

In 2011, Georgia's legislature passed a law intended to free innocent people after DNA evidence reveals someone else committed the crime. The law does not mandate the granting of a new trial when that evidence surfaces. Cook County District Attorney Dick Perryman, who opposed Inman's motion for a new trial, did not return multiple calls for comment. Inman thought the DNA would exonerate him and end his 18-year nightmare trapped in a criminal justice system he says failed to catch the real killer.

"How can it just be over? Why am I still incarcerated? What else do they want from me?" -Devonia Inman, nearly 18 years into his life sentence

A QUICK ARREST

When Inman was arrested at age 20, he still had hope that the facts would be his shield. But the years behind bars have taken their toll. "It's like they're saying, ‘Who cares if we're wrong or right? Ok yeah, he ain't the one who committed the crime, but we're going to keep him in prison anyway,’" said Inman. He came to Georgia to escape trouble. His mom had sent him to live with relatives in Adel, to get away from bad influences in California, where he had already developed a lengthy criminal record. He had lived in South Georgia for two months when Donna Brown, 40, was fatally shot after closing the Taco Bell. Known as a hard worker with a 7-year-old son at home, Brown was carrying a deposit bag with $1,732, when a gunman shot her once in the face before stealing her car and the money bag.

Taco Bell restaurant in Adel, Georgia, where the 1998 murder occurred.

Police were looking into allegations that Inman allegedly pulled a gun on another man when they turned their attention to him in the Taco Bell case. Within days, police in the small town had arrested the outsider, Inman, later charging him with Brown's murder. "There's not a shred of physical evidence, forensic evidence, no fingerprints, no blood, no DNA that ever ties him to this crime," said Cino.

WITNESSES WITH MOTIVES

The jury convicted Inman based on witness testimony, including his girlfriend's sister, a jailhouse snitch, and a Taco Bell employee, all of whom later said they lied. "Basically, I made it up, just to get him out of the picture," admits Marquetta Thomas, who was the first to implicate Inman. He was in a volatile romantic relationship with her younger sister.

"I was like, 'I'm going to get this guy.'" -Marquetta Thomas, witness who originally implicated Inman, then recanted.

She recalls telling investigators Inman arrived at her house with a whole bunch of money and blood all over him. But by the time Inman went to trial, Thomas had been arrested in an unrelated case. She realized what jail was like and recanted, instead corroborating others’ testimony that gave Inman an alibi.

WATCH: Raw video clip of Marquetta Thomas, who first implicated Inman, then recanted. She still maintains his innocence today.

"I was like,‘That boy did not kill that lady, he was with us that night,’" she recalls telling criminal investigators. She says they did not want to hear it. Now, Thomas is out of prison and has reformed her own life. She says her lies about Inman still haunt her.

"I'm sorry, please forgive me. This has gone too far. He didn't do it. I'll do anything to help free this man." -Marquetta Thomas, witness who originally implicated Inman, then recanted.

GBI Records show Taco Bell employee LarRisha Chapman first told investigators she saw nothing when she left work early on the night of the murder. Later, she changed her story telling investigators she saw Inman hiding in bushes near the victim's car and that she recognized his voice when he spoke to her. But at Inman's trial she said she was "just making that up because she was tired of the detectives calling her."

LarRisha Chapman (left) and Kwame Spaulding (right) each later claimed they falsely implicated Inman due to pressure from investigators.

Photo: Facebook Photo: Ga. Dept. of Corrections

Jailhouse snitch, Kwame Spaulding, once shared a jail cell with Inman, and brought forth information hoping to lighten his own sentence. Some of Spaulding’s information was also found in previously published newspaper articles, including one erroneous report that the Taco Bell money bag had been recovered. Later, Spaulding told the judge, "Basically everything was coerced." According to court records, he added that the detective “was telling me he'll let me go home" and "stuff to say about the man."

A $5,000 REWARD

The only witness who has not recanted her testimony is newspaper carrier Virginia Tatum, who selected Inman from a photo lineup after watching him allegedly race past her in the victim's car.

"Her story is a complete and total fabrication, I was standing right beside her." -Lee Grimes, former co-worker of Virginia Tatum.

Lee Grimes was a fellow newspaper carrier at the time and says he vividly remembers a conversation with Tatum that he believes shaped what would later become her testimony. "It was three or four weeks after the murder happened, and a car rode by with some black people in it. And she said, 'Ya know, that could be some murderers right there,'" recalls Grimes.

Prosecutors believe Donna Brown's car was driven away from the Taco Bell by her killer. It was found abandoned a few blocks away.

Tatum did not approach investigators until more than a month after the crime; Taco Bell had just announced it was offering a $5,000 reward in the case.

"She mentioned there was a reward and she said she sure would like to get that reward." -Lee Grimes, who disputes Tatum's claim that she saw Inman in the victim's car.

Virginia Tatum [Gilbert], the lone remaining witness against Inman. A former co-worker was with her at the time of the murder and disputes her account.

Photo: Valdosta Daily Times

When reached by phone, Tatum, who now goes by her married name, Gilbert, told WSB-TV and AJC she stands by her statements at the trial. She declined to comment further about her testimony. GBI agent Jamy Steinberg led the original murder investigation. Contacted recently, he also declined to answer any questions, and told WSB-TV and AJC the judge had ruled in the case; Steinberg would not comment further.

Watch WSB-TV's coverage of this investigation here.

AN ALTERNATE SUSPECT

At Inman’s trial in 2001, the judge rejected three defense witnesses who would have pointed to an alternate suspect, Taco Bell employee Hercules Brown, who was not related to the victim but was known for violence.

Hercules Brown was convicted of two nearby murders around the time of the Taco Bell crime. He also worked at the Taco Bell.

Two of Brown's friends told law enforcement he claimed responsibility for the Taco Bell murder, and a former co-worker told attorneys working with Inman that Hercules Brown tried to recruit her to help with the crime. "They were all saying the same thing. But Georgia says if all you have is that, it's not going to get admitted in court," explained Cino. Two years after Inman’s arrest for the Taco Bell murder, Hercules Brown fatally bludgeoned two convenience store workers in Adel with a baseball bat. Brown is now serving life in prison for that crime.

OLD EVIDENCE UNMASKED

Homemade mask recovered inside the victim's car.

Inman’s fate now rests on a ski mask cut from an old pair of sweatpants. The mask appears in the original crime scene photos of the victim’s car, but GBI records indicate it was left sitting in the vehicle for days after the murder.

The GBI accidentally left the mask in the victim's car for 10 days after the murder. The victim's family later called to turn it in.

It was not processed as evidence until the victim’s family found it, once the car had been returned. At the time of the murder, it was not customary for the GBI to screen evidence for the presence of saliva. In 2011, the Georgia Innocence Project convinced a judge to order the GBI to test the inside of the mask for DNA. The results matched Hercules Brown, according to the GBI's test. The evidence corroborated the three original defense witnesses who would have implicated Brown, if the judge had let them testify.

"I thought we've got it. Devonia's coming home." -Aimee Maxwell, Georgia Innocence Project Executive Director

But when they petitioned the judge for a new trial in 2014, he denied the request. Then, with no explanation, Georgia's Supreme Court refused to hear the case.

Georgia Supreme Court Order Denying Inman's Appeal in 2014

"Once you are convicted of a crime, the facts of a case don't really matter that much anymore in the court system," says Georgia Innocence Project Director Aimee Maxwell, "It's basically trying to get a court to care that you are actually innocent." During Inman’s hearing, Hercules Brown refused to testify, asserting his 5th Amendment right against self-incrimination. When the GBI questioned him about how his DNA ended up inside the mask, Brown offered no answers.

WATCH: Raw video of a GBI agent interviewing Hercules Brown about his DNA being found inside the homemade ski mask.

Brown did not respond to a recent WSB-TV and AJC request for an interview.

Out of Options

If nothing changes, Devonia Inman will spend the rest of his life in prison. His legal team is working on his version of a hail Mary, a request for a hearing in federal court that is almost never granted. Even the lawyers working to free him are astounded by his lack of legal options. “Everything we hear on the news about DNA, it should be your get out of jail free card, and the reality is that it's not," said Cino. “There is a person behind this story who is sitting in prison, possibly for the rest of his life and he's innocent. And that's scary."

Cino touches her hand to Inman's through the prison window as a show of support. WATCH: Raw clip as she speaks about his case.

Cino is now resorting to the court of public opinion. With no background in journalism, she's recording a podcast about Inman's case, hoping to gather widespread support. At his original trial, prosecutors said the evidence pointed to Inman. Now, they suggest he and Brown may have worked together, according to a 2014 court hearing transcript.

"Nobody wants to accept a mistake. But I have to live with it." -Devonia Inman