INDIANAPOLIS (AP) — The Indiana Supreme Court is taking up the appeal of a man convicted in a deadly Indianapolis house explosion.

The court is set to hear arguments Thursday in 47-year-old Mark Leonard’s appeal of his July 2015 murder and arson convictions.

Leonard was convicted in the natural gas explosion that destroyed his then-girlfriend’s home and killed two next-door neighbors in November 2012. A judge sentenced Leonard to two life sentences without parole, plus 75 years.

Leonard’s appeal contends that testimony about a separate murder-for-hire scheme in which he faces charges should never have been presented at trial.

Prosecutors say Leonard spearheaded the plot to destroy the house and collect the insurance money. Four others were charged in that scheme, including Leonard’s half brother, Bob Leonard, who was convicted in February.