It was a murder that stunned a city eternally plagued by violence — a popular French Quarter bartender gunned down in New Orleans' historic heart.

"What just happened?" Wendy Byrne said after a single gunshot rang out on Gov. Nicholls Street during a botched armed robbery attempt in 2009. Byrne fell to the pavement, where she died from a bullet to the back, days before she was to marry the love of her life.

Authorities quickly charged three teenagers in the slaying. Yet, less than eight years later, all three of them were free to walk the streets.

Drey Lewis met his own violent end Monday, slain months after he was granted "good time" parole after pleading guilty to manslaughter in Byrne's killing. Authorities have been probing whether he participated in another deadly shooting in February.

Ernest Cloud, who pleaded no contest in a Juvenile Court proceeding, has since found himself in more trouble, having pleaded guilty to two other felonies. He now awaits trial on new charges of robbery, assault and criminal property damage.

And Reggie Douglas — the one suspected of firing the gun that claimed Byrne's life — was quietly released years ago from a state mental hospital, where he was sent after being found incompetent to stand trial in the killing.

The outcome of Byrne's case came to light this week — stunning principals on both sides of the prosecution — with the killing of Lewis, who spent a total of nearly eight years behind bars before he was released in September.

Lewis, who years ago had agreed to testify against Douglas in Byrne's slaying, was killed Monday night on Eastern Street in Gentilly. He was 23.

Now, authorities are investigating whether Lewis was the same "Drey" whose name appeared Wednesday in one portion of a 17-count indictment naming a total of four defendants in four allegedly gang-related murders this year.

"I will always believe everyone's entitled to the best defense possible," said Harry Tervalon, who was an attorney for Lewis before he pleaded guilty to a lesser offense following Byrne's killing and agreed to testify against Douglas. "But it's obvious to me in this case ... that under the rules of engagement, the system has failed."

It wasn't until after Lewis' mother turned him over to police investigating the Byrne case that authorities were led to Cloud and Douglas, District Attorney Leon Cannizzaro said Thursday.

Evidence suggested that Byrne, 39, had been shot by Douglas and that Lewis and Cloud had accompanied the gunman in more passive roles.

Lewis and Douglas were the only two charged as adults, having been 16 at the time. Cannizzaro said the actions of Lewis' mother combined with his willingness testify against Douglas made the state amenable to cutting a deal with Lewis.

Lewis pleaded guilty to manslaughter in September 2012 and received a 10-year sentence with credit for the time he had spent in jail since his arrest. He ultimately served about 80 percent of his sentence.

But prosecutors never got the chance to put Lewis on the stand.

In 2011, Criminal District Court Judge Benedict Willard deemed Douglas to be irreversibly incompetent and shipped him off to the East Feliciana Parish state mental hospital.

Willard's ruling followed an evaluation by several mental health experts and testimony from Dr. Brad McConville, a Tulane University psychiatrist who described Douglas as "essentially totally illiterate."

Douglas said he often heard the soft voice of his deceased grandmother in his head, and McConville found he could neither understand the legal proceedings he faced nor assist in his own defense.

A later exam found Douglas to have an "irreversible intellectual impairment," with an IQ of about 50 — indicating "moderately severe mental retardation."

Douglas grew up in the St. Bernard housing development, according to tattoos on his hands. He had lived with his troubled mother, the doctors reported. They suspected fetal alcohol syndrome in his features.

Then, East Feliciana Parish Judge George Ware ordered Douglas civilly committed to the state Department of Health in August 2012. Soon afterward, the state agency placed Douglas at the Harmony Transitional Center, a Baton Rouge facility, court records show.

In April 2014, East Baton Rouge Judge R. Michael Caldwell granted Douglas his conditional discharge, assigning him to the home of a cousin in Lafayette, even though he deemed Douglas "gravely disabled and a danger to others as a result of mental illness."

Willard, who presided over the Wendy Byrne murder case, lost oversight of Douglas once he was committed civilly. Prosecutors still could seek a new hearing to revisit his competency to stand trial.

Cannizzaro said Thursday his office planned to consult with state health officials about whether Douglas' competence could be restored.

However, regardless of whether Douglas is ever deemed competent to face a murder trial, aspects of his case frustrated both the prosecution and the defense.

Even though a letter from state health officials to Willard explaining Douglas' 2014 release listed Cannizzaro's office as a recipient, the DA said his staff didn't learn of the defendant's fate until word of Lewis' death spread.

He said health officials did not make him aware that Douglas was apparently well enough to be discharged from their care, a troubling situation that has occurred in other cases. Otherwise, Cannizzaro might have started the process of determining whether Douglas was well enough to face trial sooner, preferably before losing a key witness in Lewis.

Meanwhile, Lewis' attorney, Tervalon, found irony in the fact that Douglas was freed from custody at a state facility before a key witness against him was.

"That is not the way the system is supposed to work," said Tervalon, who represented Lewis along with attorney Eric Malveau. "All the work Eric and I did (in negotiating a plea) was to save Drey from dying in Angola, and he does more time than" Byrne's purported shooter.

When he died, Lewis had also done more time than Cloud, who served two stretches at the Bridge City Center for Youth before he was released on his 21st birthday in October 2015.

Cloud, who was 15 when Byrne died, has not managed to avoid brushes with the law since then.

In between stretches at the Bridge City complex, where prosecutors hoped he would gain an education or a trade, he was jailed on suspicion of receiving stolen things in Jefferson Parish. He pleaded guilty to that in 2014 in exchange for probation.

In September, he pleaded guilty in New Orleans to illegal possession of stolen things, again receiving probation. He was then arrested in late November on a warrant accusing him of simple assault, simple robbery and simple criminal damage after he was accused of threatening to kill a woman; he awaits trial behind bars.

"It seems from every juncture of this road we have been stymied trying to get justice for Wendy Byrne," Cannizzaro said Thursday.

Irv Magri, the president of the Crimefighters of Louisiana victims' rights organization, echoed that sentiment when asked about Byrne's case.

"To say this is an appalling miscarriage of justice would be a mild statement," Magri said. "We cheapen human life by allowing this situation to exist."

— Staff writer Jim Mustian contributed to this report. 

Follow Ramon Antonio Vargas on Twitter, @RVargasAdvocate.

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