More than seven years after 16-year-old Gervais “Gee” Nicholas was gunned down amid fisticuffs at a Tulane Avenue nightclub, a trial began Wednesday for one of the accused triggermen in a case long troubled by witness problems, including allegations by one witness that the lead homicide detective deliberately coaxed a positive identification from him in a photo lineup.

Joseph Morgan, 24, was a day over 17 when he and Taivon Aples were accused of killing Nicholas outside the Chat Room nightclub on Jan. 12, 2008, after a fight broke out and club security locked the doors.

A few people identified Morgan or someone who looked like him as the first of two shooters, though ballistics showed only one weapon, a .380 pistol, was used to kill Nicholas, according to testimony Wednesday.

One of those witnesses, club DJ and bouncer Sandy Ruffin, recanted his identifications at a hearing just before Aples was set to go to trial in 2012, saying “he was coerced by Detective Catherine Beckett when he made his photo identification,” according to a court filing from District Attorney Leon Cannizzaro’s office.

Aples would quickly plead guilty as an accessory to murder and go free on credit for time served.

When Morgan was slated for trial in 2013, Ruffin claimed he never saw the shooting and had just followed Beckett’s lead in his earlier statements. Criminal District Court Judge Arthur Hunter halted that impending trial and sent potential jurors home.

By then, Morgan was free, released on a motion by his attorneys for a speedy trial after the continual delays, many of them at the request of prosecutors.

This April, Morgan was arrested again, along with two others, after the daytime murder of 18-year-old Herbert Tennessee, who was fatally shot from a white Nissan while running down Constance Street in the Irish Channel.

Tennessee, a student at Landry-Walker High School, died two days later, on April 29.

Cannizzaro’s office has yet to accept that murder charge against the diminutive Morgan, who sat in a white dress shirt on the first day of testimony Wednesday in the 2008 killing, one of the oldest lingering cases at the criminal courthouse.

Assistant District Attorney Elizabeth Kilian said Ruffin has since double-flipped, going back on his earlier statement recanting his original photo identification.

Ruffin is expected to testify Thursday.

In the meantime, Beckett, now retired from the NOPD and working as a forensic investigator for Orleans Parish Coroner Jeffrey Rouse, took the stand to deny ever coaxing Ruffin’s identification by tapping her finger at a photo of Morgan.

“Absolutely not true,” she testified.

Hunter, the judge, refused to allow the jury to hear about Beckett’s rocky history with the NOPD — specifically, her firing over her role in the case of five officers accused in the fatal shooting and burning of Henry Glover’s body in the wake of Hurricane Katrina and what federal prosecutors labeled an NOPD cover-up.

Beckett was fired by then-NOPD Superintendent Ronal Serpas, ostensibly for violating department policies. Serpas ruled she should have informed her superiors and federal prosecutors that she planned to testify on behalf of Robert Italiano, a retired NOPD lieutenant who eventually was acquitted of helping cover up how Glover died.

During her testimony in that case, Beckett accused another former officer of perjury before a grand jury; Serpas said she also should have reported that to federal authorities.

Beckett filed a federal lawsuit in 2012 against Serpas and the city. She was reinstated in 2013 but left the force soon thereafter.

She testified Wednesday about a “chaotic scene” at the Tulane Avenue club, where five shell casings lay on the ground near the body of Nicholas.

“He was shot by Mr. Morgan at least two times, and then by Mr. Aples, and then by Mr. Morgan again,” Beckett testified, citing witness accounts.

Earlier, prosecutor Kilian argued to the jury that the case was all about three witnesses who identified Morgan. She said Nicholas’ promising life was cut short after he returned to New Orleans following a period in Texas after Katrina.

“All he wanted to do was get back to his environment,” Kilian said. “Joseph Morgan shot the victim in cold blood. Nobody is going to say the victim had a gun. Nobody is going to say he instigated this. This was a completely unwarranted shooting of a 16-year-old boy who had a bright future.”

Nandi Campbell, one of Morgan’s defense attorneys, painted a different picture, telling the jury that Nicholas was “tatted up with (gang) signs.”

Mostly, though, Campbell cast suspicion on the witness accounts.

“Every witness tells a different story about what happened, and I’m not talking about the color of my buttons. I’m talking about significant differences in the story,” she told the jury.

Follow John Simerman on Twitter, @johnsimerman.