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SOUTH BEND, Ind. (June 28, 2015)– With the technical evidence out of the way, jurors in the Mark Leonard double murder trial will this week hear from investigators who put the pieces together, and a key co-conspirator, in the search for answers to the Richmond Hill explosion.

Leonard is charged with being the driving force to blow up then-girlfriend Monserrate Shirley’s house in the fall of 2012 in the pursuit of a $300,000 home insurance payoff.

Instead, two people were killed, 80 homes were damaged or destroyed at a loss of $4.4 million and Leonard and four of his friends were accused of more than 50 counts of arson, conspiracy, insurance fraud and murder.

Jennifer and Dion Longworth were killed in the explosion and fire that consumed their home next to Shirley’s at 8349 Fieldfare Way.

Up until this point a jury in South Bend, where the case was moved due to extensive pre-trial publicity and the anticipated difficulty in finding a panel made up of persons who literally did not hear the explosion on the night of November 10, 2012, has been witness to a parade of Richmond Hill residents, Citizens Energy experts and crime lab specialists who have testified about the events of that fateful Saturday night and the immediate investigation that determined the blast was no accident.

Now, the St. Joseph Superior Court jury will listen to the testimony of the investigators who wove the evidence thread that linked the conspirators with the fatal plot.

“Lieutenant (Mario) Garza did the actual formal origin and cause in this case and made his determination and so the jury will hear about that Monday,” said Deputy Prosecutor Denise Robinson, referring to the lead arson investigator from the Indianapolis Fire Department, “and then we’ll move to the actual police investigation which is the homicide detective and consists of things that most ordinarily would be quoted with a homicide case, cell phone records, DNA, co-defendant, that sort of thing.”

Veteran Homicide Detective Jeff Wager caught the case that night and has been primarily detailed to its investigation ever since.

200 witnesses, more than 2500 pieces of evidence and 30,000 pages of documents make up the most extensive investigation in Marion County history, and the star witness is yet to testify.

Shirley will take the stand by mid-week and is prepared to point the finger at her ex-boyfriend as the main motivator behind the explosive plot.

“I’ve said all along, ever since she took a plea agreement and agreed to testify for the State, that she provides that inside information that we didn’t otherwise have,” said Robinson. “We believe we had a solid case before she agreed to cooperate but once she did it gives you an inside perspective.”

In January, more than two years after she was arrested alongside Leonard when she dropped her daughter off at school days before Christmas of 2012, Shirley signed a plea agreement, negotiated by her attorney, James Voyles, to testify against her co-defendants in exchange for a guilty plea to reduced charges that could still conceivably send her to prison for decades, or no additional time at all.

Through her attorney, Shirley claimed she was intimidated and perhaps physically manhandled by Leonard and therefore was powerless to resist his schemings.

Leonard’s attorneys have already attempted to head off such claims, eliciting from John Shirley his ex-wife’s propensity to make independent decisions and operate complicated hospital equipment as an Intensive Care Unit nurse, setting the stage for an argument that it was she, and not her ex-boyfriend and his half-brother, Bob Leonard, Jr., who tampered with natural gas safety systems at her home the day it filled with gas and exploded.

Shirley also testified that after his ex-wife hooked up with Leonard, her demands for money and child support payments increased and he was forced to work three jobs to meet his obligations.

Investigators found several indications of Leonard’s attendance at Indiana casinos in the aftermath of the blast and Leonard and Shirley awaited news of their plot at the Hollywood Casino in Lawrenceburg, rushing home after receiving a phone call from a neighbor, where they were captured on tape by a FOX59 News camera at nearby Mary Bryan Elementary School with other evacuated residents early the next morning.

Shirley’s testimony against his former wife’s former boyfriend who is accused of blowing up his young daughter’s house came from a witness stand less than 15 feet away from the accused man seated at a table between his public defenders in a basement courtroom 140 miles away from the house where everyone used to live.

It’s the same witness stand where this week Monserrate Shirley will sit, between her former lover and a jury of his peers, and tell under oath what happened in the months and days and hours before and after a blast that literally rocked the south side of Indianapolis and killed the people next door.