Two cousins accused in the robbery, beating, kidnapping and killing of an elderly Highland Road couple in 2015 might face two different East Baton Rouge juries beginning on the same date — during simultaneous trials held in the same courtroom.

Ernesto Llerena Alonso, 44, and Frank Garcia, 49, are each charged with two counts of first-degree murder in the killing of Denis "Bubbie" Duplantier, 71, and Suzanne "Suzy" Duplantier, 70. Their bodies were found Oct. 19, 2015, in the backseat of their red pickup at a Hammond gas station.

Alonso lived in an apartment above a barn on the couple’s property on Nicholson Drive and did landscaping work for them. He was arrested in Florida on Oct. 21, 2015, Garcia, of Hollywood, Florida, was arrested less than a month later, on Nov. 18.

The dual-jury proposal, in which each panel of jurors would be tasked with deliberating the guilt or innocence of a separate defendant, is a novel proposal for the East Baton Rouge criminal court. Several Baton Rouge lawyers, including District Attorney Hillar Moore III, said they couldn't recall a two-jury system ever being used in the 19th Judicial District Court.

Dwight Doskey, a Capital Defense Project of Southeast Louisiana lawyer who represents Alonso, told state District Judge Trudy White on Tuesday that he expects the two Spanish-speaking men to be tried separately and that a two-jury system is a distinct possibility.

"They (prosecutors) know they have to sever the two cases," he said outside the 19th Judicial District courtroom.

Doskey, however, said using two separate juries simultaneously comes with its share of risk, including upping the chance of a mistrial if there is a slip-up.

"It's really a very difficult situation to manage," he added.

Assistant District Attorney Ron Gathe, who is prosecuting the case, said Tuesday a two-jury system would be a cost-effective way of trying the two men. A number of witnesses would be coming from Florida, he noted.

Moore, the district attorney, said it's too early to predict whether two juries will be utilized in the Duplantier case because the defense has not yet filed a motion to sever the men's cases.

Both Alonso and Garcia have been held without bail since they were returned to Baton Rouge from Florida, where both were arrested. After consulting with the victims' family, prosecutors announced last year that they would not pursue the death penalty in the case in order to speed up the process. If Alonso and Garcia are found guilty of first-degree murder, they would be sentenced to life in prison.

Garcia is represented by the East Baton Rouge Parish Public Defenders Office.

A safe inside the Duplantier home was found open, with cash missing. Investigators believe Alonso and Garcia entered the home and beat the couple to obtain the information needed to open the safe. Blood was found in several rooms, police have said.

A large amount of cash and a number of unspecified items believed to have ben stolen from their Highland Road residence were discovered in Garcia's house in Florida, according to authorities.

Alonso's white pickup truck was captured on surveillance video as it followed the Duplantiers' truck into the Petro truck stop in Hammond, according to police. Alonso's truck was recovered at Garcia's house.

Two juries hearing the severed cases at the same time present potential logistical challenges in a courtroom built for just one set of jurors, who'd also be sent shuffling in and out of court whenever prosecutors presented evidence against just one of the cousins.

It would also present an organizational challenge for the judge in the case, Trudy White, who would need to guard constitutional protections for both defendants and juggle their potentially conflicting interests, said Bobby Harges, who teaches criminal defense at Loyola University College of Law in New Orleans.

Harges, who's taught and practiced law for 30 years, said he couldn't recall a single instance where it'd been done before.

"Nothing constitutionally prohibits it," Harges said."But this process is unusual."

A search of cases in the Westlaw database turned up two trials with dual juries in Louisiana in the past 40 years: A 2000 case in Orleans Parish and a 1981 case in East Baton Rouge Parish, both involving co-defendants charged with armed robbery.

Appellate courts upheld the practice in both instances.

Even with the separate panels of jurors heading in and out of the courtroom as different evidence is presented, the scheme still runs the risk of introducing testimony against one of the cousins that might improperly bias jurors against the other, said Kelly Carmena, a Southern University Law Center professor and former public defender.

"You still have some of the same constitutional issues, the prejudicial issues that come up if you didn't sever the two defendants and tried them together," Carmena said.

W.J. Leblanc, a former Jefferson Parish prosecutor, recalled holding a judge trial and a jury trial simultaneously, in 1990.

A jury convicted William Fontanille, of manslaughter at the same time a judge convicted Kerry Myers of murder in the 1984 fatal beating of Myers' wife inside their Harvey home. In December, Gov. John Bel Edwards ordered Myers, the inmate editor of the prison magazine The Angolite, freed from prison.

"It really wasn't all that complex. It just wasn't. There were a few times when something really wasn't relevant to the jury, so the jury came out," Leblanc said. "There was a lot of hoo-ha over it, but it was basically much ado about nothing."

Leblanc said he's never heard of two juries weighing the fate of separate defendants at once, and that it would present "some logistical hurdles," but could make sense.

"If you have a key witness that's dying, and maybe won't be around for a second trial, well guess what?" Leblanc said. "That's a very innovative way of doing it as long as you're not violating somebody's rights."

Advocate staff writer John Simerman contributed to this report.

Follow Joe Gyan Jr. on Twitter, @JoeGyanJr.