A former exotic dancer pleaded guilty Thursday in the 1984 slaying of Gary Kergan, claiming she lured him to her apartment and fed him poisoned wine in a conspiracy to rob and kill the Crowley businessman.

Leila Mulla, 48, of Astoria, N.Y., admitted in court that she helped poison Kergan, whose body has never been found.

Sentenced to 30 years in prison, Mulla agreed to cooperate with the state in the prosecution of Ronald Dalton Dunnagan, 65, of Bossier City, who has been arrested twice in the case but is not under indictment.

Kergan, 34, was last seen alive on Nov. 29, 1984, at a Byron Street apartment shared by Mulla and Dunnagan in north Baton Rouge, police have said.

Kergan’s Cadillac El Dorado was found several days later abandoned on Severn Avenue in Metairie in Jefferson Parish. A significant amount of blood was found in the trunk of the car.

He was declared legally dead by the courts in 1986.

Prosecutor Dana Cummings said inside state District Judge Mike Erwin’s courtroom Thursday that Mulla, who lived with Dunnagan at the 2956 Byron St. apartment, worked as a dancer at the Night Spot Lounge on Plank Road, where she met Kergan. The prosecutor said Mulla conspired with Dunnagan to rob and murder Kergan.

Mulla left the lounge with Kergan on Nov. 29, 1984, and “lured” him back to the apartment, where Dunnagan was hiding, Cummings said.

“Dunnagan poisoned the victim’s wine, and Mulla gave it to him,” Cummings said. “Dunnagan dragged him into another room to complete the murder.”

Cummings said Dunnagan placed the body in the trunk of Kergan’s car to dispose of it.

“Ma’am, is that about what happened?” Erwin asked a shackled Mulla, who wore dark green prison clothes.

“Yes, sir,” she answered in a soft voice.

Police have said Kergan had about $2,000 cash in his possession and jewelry valued at more than $8,000 on the night he disappeared.

An affidavit of probable cause says Mulla authored a hand-written diary that indicates the Kergan robbery was a planned event between her and Dunnagan.

Dunnagan was Mulla’s boyfriend, according to court records.

But Mulla’s attorney, Frank Holthaus, told reporters Thursday that Mulla was a teen runaway and a victim of human trafficking at the hands of Dunnagan, who prostituted Mulla and other girls for money. Mulla did not receive the money, Holthaus said.

“It was for the man who had taken her — Ronald Dunnagan,” he said.

Mulla and Dunnagan were first arrested in Las Vegas in December 1984 and accused of plotting to rob Kergan but were released in March 1985 after then-East Baton Rouge Parish District Attorney Bryan Bush declined to prosecute the pair because of a lack of evidence.

Mulla and Dunnagan were arrested again in December 2012 after DNA testing of blood found in the trunk of Kergan’s car confirmed it belonged to him. That testing was not available at the time of the crime. Mulla also admitted her involvement in the crime in statements she gave to Louisiana authorities in December 2012 in New York, according to court records.

Mulla was booked in late 2012 with second-degree murder, simple robbery and criminal conspiracy. Dunnagan was booked on counts of first-degree murder, simple robbery and criminal conspiracy.

An East Baton Rouge Parish grand jury indicted Mulla in April 2013 on a first-degree murder charge but took no action against Dunnagan. Mulla was not cooperating with the state at that time, East Baton Rouge Parish District Attorney Hillar Moore III noted.

Dunnagan was released from jail last year after the grand jury took no action against him. The first-degree murder charge filed against Mulla by the grand jury carried two possible penalties: death by lethal injection or life in prison. Prosecutors had not announced whether they would seek the death penalty.

Mulla, who pleaded guilty Thursday to manslaughter, worked as a nurse in New York prior to her second arrest, Holthaus has said. News accounts at the time of the 1984 arrests described Dunnagan as a drifter.

Cummings said Mulla must serve at least 25 years and five months of her 30-year sentence.

Moore said Mulla will be interviewed, then the matter will be presented to a grand jury.

“They’ll make the decision whether we have enough evidence to go forward,” he said.

Holthaus said Mulla is remorseful for her actions in the Kergan case, although she offered no apology to Kergan’s family. Holthaus said he advised Mulla not to make any statement because such statements typically are met with much skepticism.

Moore credited the Kergan family’s tenacity with helping to solve the case.

“This case probably would have gone unsolved but for the dogged efforts of this family,” he said.

“The family has worked this case for 30 years,” Cummings added. “They have been persistent.”

Kergan’s son, Wade, was 10 when his father was murdered.

“It’s been really tough,” Wade Kergan said as he choked up outside the 19th Judicial District Courthouse. “It feels amazing to have closure for the case and have some justice.”

Moore also praised investigators and cold-case detectives, mentioning Baton Rouge police Detective John Dauthier by name.

Gary Kergan’s brother, Ted Kergan, said he lost not only his brother but his business partner and best friend. They owned a chain of Sonic Drive-In restaurants in south Louisiana.

Ted Kergan said Mulla’s guilty plea brought him both relief and anger, although he agrees with the 30-year sentence.

“I think that’s just. I think that’s justice,” he added.