Fulton County District Attorney Paul Howard has reopened a controversial police shooting case for review after a Channel 2 Action News-Atlanta Journal Constitution investigation uncovered new evidence and witnesses whom the grand jury did not see.

Union City Police Officer Luther Lewis shot and killed 19-year-old Ariston Waiters in December 2011.

Waiters took off running when police arrived to break up a fight between teenagers after shots were fired into the air.

Lewis chased Waiters, got him on the ground and then shot him twice in the back.

"I just went to screaming and hollering no, no, no. My son is not dead," Freda Waiters says.

More than three years have passed, but her wounds have not even begun to heal.

She says she keeps hearing new details of the case that the grand jurors who cleared the officer never heard.

"Even if the deceased in this case had physically defended himself... he had a right to do it because he was being illegally arrested," Howard said.

In May 2012, a Fulton County grand jury opted not to indict Lewis on the recommended charges of felony murder, aggravated assault, false imprisonment and violation of oath.

"The way he said the story happened, that's impossible. The forensics show it," Waiters said.

New video shows reenactment 

In a never-before-seen video, Lewis showed the GBI agents his version of the shooting, by re-enacting how Waiters grabbed his gun.

Lewis can be heard telling the agents, "My mind is telling me he's fixing to pull a gun out, and I'm like frickin' flipping out."

He continues the demonstration crouched on the floor with an agent beneath him to show how Waiters allegedly reached behind and upward toward the gun, while still lying face down.

"I went with everything I had, like bam bam," Lewis said, demonstrating the way he fired his service weapon.

The video differed from earlier statements that Lewis had given, so much so that an expert called his statements "self-contradictory" and inconsistent with the forensic evidence.

Michael Levine has been a consult for the Fulton County district attorney on numerous cases. He spent 40 years in law enforcement, and is considered a national expert.

In his report on the Waiters case, Levine recommended charging Lewis with making false statements, calling Lewis' actions contrary to all professional law enforcement standards and citing "a disregard for human life that is unacceptable."

"It's not sat right with me from the first time I arrived on the scene," Union City Police Officer Chris McElroy says.

McElroy was a lieutenant at the time of the shooting, and was the first supervisor to arrive at the scene. He has never before spoken publicly about what he heard and saw.

"There's a lot of things that need to be answered," McElroy said. "I think Mr. Waiters died senselessly, and his family deserves closure."

McElroy told investigative reporters Jodie Fleischer and Brad Schrade that he's never believed that the shooting was justified, based on Lewis' statements immediately after the shooting.

McElroy said that initially, there was no mention of a struggle over the officer's gun.

"He was unable to pull his hands out from underneath him. He didn't know what was under there, so he shot him twice," McElroy said.

He said he expressed his concerns to several other command officers and Chief Chuck Odom, who directed him not to write a statement and later bragged about keeping Lewis out of prison.

Odom declined to be interviewed for this story.

McElroy's involvement in the case

The Georgia Bureau of Investigation investigated the shooting, and did not interview McElroy.

"I was surprised I didn't get called by the GBI, to be honest with you," said McElroy, "I was the supervisor on duty, I was the first arriving supervisor on the scene. You would think that someone investigating it would want to talk to me."

Howard's investigators did interviewed McElroy before the case went to a grand jury, but did not call him as a witness.

Howard said he was not aware of McElroy's statement, or that of another command officer who raised concerns about Lewis, until Channel 2 and the AJC brought those statements to Howard's attention.

"We would have loved to have presented that to a grand jury," Howard said. "If it was there and somebody didn't bring that to my attention, I deem that as a mistake."

Channel 2 and the AJC tracked down a half-dozen officers, many of whom asked not to be quoted for fear of retaliation from the department. Each told part of the story and recalled issues involving Lewis.

A few months before the Waiters shooting, on a call about a suspicious person in the Brookstone neighborhood, McElroy says he rolled up on Lewis with his gun pointed in another suspect's back.

"Officer Lewis explained that he suspected the young man had something in his pocket and couldn't get his hands out and said, 'I was fixing to shoot him,’" McElroy said. "I counseled him on his choice in use of force."

Lewis also used force on Royal South Parkway about a year before the Waiters shooting.

He fired three to four rounds in the woods, claiming that someone had shot at him.

Only the officer’s bullet casings were found.

Investigators at the time questioned whether Lewis’ account really happened, and told Channel 2 that they found evidence to the contrary, but were directed not to interview Lewis about it and not to write up an internal affairs report.

Was Lewis fit for duty?

In an interview with the district attorney's investigators after the Waiters shooting, Captain Michael Jones said he had already counseled Lewis a year earlier, concerned that he might have been suffering from post-traumatic stress disorder after returning from a military deployment.

Another officer had brought it to Jones’ attention after observing Lewis shaking during a traffic stop.

"Everyone had concerns that he had issues," McElroy said.

Just a few weeks before the Waiters shooting, a sergeant wrote Lewis up after a raid in which Lewis claimed that he saw movement in a house that turned out to be empty. Officers believed that Lewis lied as an excuse to get permission to enter the home.

None of the above-mentioned incidents appeared in Lewis' department disciplinary file.

Union City Assistant Police Chief Lee Brown said he was not aware of any questions about Lewis’ fitness for duty before the Waiters shooting.

"Several officers may have noticed something and spoke to Officer Lewis, but none of the officers that I can recall came to any of the command staff," said Brown.

Howard said that if incidents were deliberately kept out of Lewis’ official department files, that would be a problem that needs investigating.

"The files that we received from the police department were not that helpful," Howard said. “The impression that I'm receiving from what you are reporting is that in many instances, we were misled.”

The district attorney said he was not aware of Lewis' history, so neither was the grand jury that cleared Lewis.

"Listening to what you're saying today, I'm going to be looking very closely at re-presenting it," Howard said.

Howard believes that the grand jurors were persuaded by Lewis himself, who attended the entire 12-hour proceeding.

"What I told the grand jury that night is the type of person I am. Had someone else had a gun and been shooting that night and Ariston Waiters was standing there, I would have put him behind me and I would have (taken) a bullet," Lewis told Channel 2 Action News in 2012.

He said he wasn't out to hurt anyone.

"The second I had to pull that trigger, and I use ‘had’ because I had no choice, I know in my heart I was not walking away, I made peace with God," said Lewis.

Officer Lewis has always maintained that the shooting was justified and that he was in fear for his life.

He left the Union City Police Department last year, amid concerns about PTSD following the Waiters shooting.

But because that was considered a voluntary resignation, the department never reported it to the state, and he is still certified to work in another department.

Lewis refused requests to talk about the case now.

Fleischer and Schrade contacted Howard on Wednesday. By Thursday morning he had called GBI Director Vernon Keenan and each reopened their respective cases.

Private investigator T.J. Ward helped the Waiters family acquire the documents from the case.

"I think it was a poor investigation. I think they didn't bring out some of the information that they could have," Ward said. "I think there were people that need to be interviewed that they didn't interview. I think somebody's protecting Luther Lewis."

Freda Waiters said she just wants everyone to know the truth.

"My son is dead and gone, I can't get him back. But I am going to get justice for my son," she said.