By The Associated Press

INDIANAPOLIS — All three defendants charged with causing a 2012 explosion that killed two people and devastated an Indianapolis neighborhood object to prosecutors’ proposal to hold a single trial for them before separate juries, arguments their attorneys filed by Friday indicate.

Attorneys for Monserrate Shirley, Mark Leonard and Bob Leonard argue there’s no proof a single trial would save time or resources, but that it would pose greater risk of possible harm to their clients. Shirley and Mark Leonard used to be a couple, and the Leonards are brothers.

Shirley’s attorney, James Voyles, said in a filing late Thursday in Marion Superior Court that concurrent trials — ones occurring at the same time — would make it difficult for his client to get a fair trial on murder and arson charges. He has argued Shirley was under Mark Leonard’s control when the defendants allegedly rigged a natural gas explosion in her home in November 2012 in hopes of collecting insurance money.

“The complexity of the case makes concurrent trials a recipe for mistrial disaster,” Voyles wrote.

The defense attorneys have argued that such a large and complicated case is unsuitable as a test case for concurrent trials in Indiana. Prosecutors have estimated they have about 250 witnesses and more than a thousand pieces of evidence for the trials, which currently are scheduled to begin in mid-June.

Friday was the deadline for defense responses to the prosecutors’ plan. It’s not clear when Judge Sheila Carlisle will rule on the matter.

Prosecutors proposed holding one trial with separate juries after Carlisle agreed to give each suspect a separate trial. They said the cost and resources needed for three separate trials would be prohibitive.

Deputy Marion County Prosecutor Denise Robinson has said she will ask for no fewer than 18 jurors per case, bringing the total to at least 54 and likely requiring such a trial to be held at an auditorium or some other outside venue.

The defendants face dozens of charges including murder and arson for the explosion that killed Shirley’s next-door neighbors, John and Jennifer Longworth, and damaged scores of homes in the Richmond Hill subdivision on the city’s far south side. All three have pleaded not guilty.