SOUTH BEND, Ind. » A judge is set to decide Friday whether an Indianapolis man convicted in a house explosion scheme that killed two neighbors will be sentenced to life in prison without the possibility of parole.

Prosecutors have said they don’t expect Mark Leonard to ever leave prison no matter what the judge rules, since he faces at least 45 years on each of two murder convictions.

A jury in South Bend convicted Leonard, 46, of murder, arson and conspiracy charges on July 14. The explosion on Nov. 10, 2012, damaged or destroyed more than 80 homes in the Richmond Hill subdivision on the south side of Indianapolis and killed 34-year-old John "Dion" Longworth and his 36-year-old wife Jennifer.

St. Joseph County Superior Court Judge John Marnocha on Monday ruled life without parole was a possibility, but that could change after he receives the pre-sentence report. He said that report could contain mitigating circumstances he should consider.

Leonard’s lawyers had asked Marnocha to rule life without parole wasn’t a possibility, arguing prosecutors hadn’t proven the sufficient mitigating factors. Marnocha ruled they did, describing Leonard as the "prime mover" in the scheme.

The mitigating factors Marnocha cited were the use of an explosive device, the killings of multiple people and the fact that Dion Longworth burned to death.

The coroner ruled Jennifer Longworth was killed instantly in the blast.

Marnocha said last month that the minimum sentence Leonard could face was 45 years in prison and the maximum would be 1,488 years, adding the appropriate sentence "might be somewhere in between."

Prosecutors alleged Leonard was the mastermind behind the explosion, plotting with his then-live-in girlfriend Monserrate Shirley and his half brother Bob Leonard to use natural gas and gasoline to blow up the home so they could collect $300,000 in insurance.

Shirley testified against her former boyfriend, and Bob Leonard is scheduled to go on trial on Jan. 19 on the same charges his brother faced. His trial is being moved to Fort Wayne because of extensive media coverage in Indianapolis, the same reason Mark Leonard’s trial was moved to South Bend.

Defense attorney Diane Black has argued that Mark Leonard wasn’t the main person planning the explosion and that life without parole would be too disparate a sentence from the one Shirley will receive. Black argued Shirley was just as involved, but prosecutors had portrayed her as a victim unable to make a decision.

Shirley, who pleaded guilty to two conspiracy charges as part of a plea agreement, faces a possible sentence of 20 to 50 years in prison.