A prosecutor told jurors Thursday there is only a 1-in-9.76 quadrillion chance that DNA found on the bodies of Baton Rouge murder victims Renee Newman in 2002 and Florida Edwards in 1999 belongs to someone other than Jeffery Lee Guillory.

“I’m not real strong in math, but that’s a whole bunch of zeroes,’’ East Baton Rouge Parish Assistant District Attorney Dana Cummings said in her opening statement to the jury at Guillory’s second-degree murder trial in the strangulation of Newman, 46.

Attorneys for Guillory, a suspected serial killer, had hoped to argue to the jury that there is a chance convicted Baton Rouge serial murderer Sean Vincent Gillis could have been responsible for Newman’s death, but state District Judge Tony Marabella earlier Thursday barred the defense from making any reference to Gillis.

The judge essentially ruled that Gillis, who reportedly associated with Newman, is irrelevant to the case.

“We think it’s highly relevant,’’ Franz Borghardt, one of Guillory’s attorneys, said after court. “It isn’t just something that we made up.’’

Robert Savage, who also represents Guillory, had argued there are “overwhelming’’ similarities between Gillis’ crimes and the Newman slaying.

“Sean Gillis was part of the investigation’’ into Newman’s death, Savage told the judge. “We have a right to present this evidence.’’

Cummings countered that the defense was trying to “sensationalize’’ the trial.

“This is a very blatant attempt to confuse this matter and turn this into a circus,’’ she argued. “They are entitled to present a defense, but not one that is bogus and lame.’’

Borghardt told Marabella the state 1st Circuit Court of Appeal in Baton Rouge will be asked to review his ruling, but the judge refused to halt the trial.

After court, Borghardt called Marabella’s ruling “justice denied.’’

What Borghardt eventually argued to jurors is that they can dislike Guillory, but they should not judge him based on that disdain.

“You can hate him. I’m giving you permission to do it. But it’s no substitute for evidence,’’ Borghardt told the 12 jurors and two alternates.

Borghardt also attacked the state’s DNA evidence, saying DNA can be a “magic bullet’’ or “possibly just a piece of evidence that may wrongfully convict someone.’’

Guillory, 45, faces an automatic sentence of life in prison if convicted as charged in the killing of Newman.

The trial resumes Friday and is expected to last through the weekend.

Guillory already is serving a 50-year prison term in the second-degree robbery and attempted second-degree murder of a woman in Lafayette in late 2007. He was convicted in that case in early 2010.

The woman, Johnnie Rose Martinez, will testify, Cummings told the jury.

Gillis is serving life terms in the 2004 strangulation and mutilation of Donna Bennett Johnston, of Baton Rouge, and in the 1999 killing of Joyce Williams, also of Baton Rouge. She was killed in Port Allen.

Authorities have said Gillis confessed to killing eight south Louisiana women between 1994 and 2004.

Baton Rouge police Sgt. Chris Johnson testified Thursday at a pretrial hearing on the Gillis matter that he interviewed Gillis in April 2004, but Gillis never confessed to killing Newman or Edwards.

“I knew if he had killed those women, he would have admitted to it,’’ Johnson said.

The detective said Gillis was never considered more than a “person of interest’’ in the Newman killing.

Guillory was arrested in December 2009 in the deaths of Newman, Edwards and Sylvia Cobb.

Newman’s body was found April 11, 2002, behind the old Maison Blanche/Goudchaux’s building on Laurel Street.

Cummings said Newman was strangled with her own shirt, which was pulled up around her neck.

Jurors watched a 20-minute video of the crime scene, which showed Newman’s body covered in ants in a trash-strewn flower bed.

The body of Edwards, 36, was discovered Sept. 3, 1999, inside the old Dynasty Lounge on North Boulevard. She died of strangulation and a blow to the back of the head, police said.

Cummings said Newman and Edwards led high-risk lifestyles, and the prosecutor argued that Guillory “picked on’’ such women.

Cobb’s body was found July 25, 2001, inside an abandoned house on North Acadian Thruway West. She also was 36.

Guillory remains a suspect in several other unsolved killings of women in Baton Rouge that occurred in the late 1990s and early 2000s, authorities have said.