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SOUTH BEND, Ind. (June 26, 2015)– Now that the technical framework for the fatal 2012 Richmond Hill explosion has been laid for jurors in a South Bend courtroom, the Prosecution is ready to explain how it pinned the conspiracy on lead defendant Mark Leonard, and it will count on his former lover to seal the deal in the coming week.

Leonard is accused of masterminding the blast that leveled girlfriend Monserrate Shirley’s home, destroyed or damaged 80 neighboring residences at a loss of $4.4 million and took the lives of the people next door.

As testimony concluded Thursday, St. Joseph Superior Judge John Marnocha denied a Defense motion for a mistrial based on a federal agent’s miscalculations of the speed with which excess natural gas filled Shirley’s home on November 10, 2012, and the jury heard from witnesses who explained how critical pipes and valves were tampered with to introduce the fuel into the doomed dwelling.

While the State struck the discredited agent’s name from its list of witnesses, another utility expert explained to the jury how much gas he estimated entered the home.

CEG Director of Energy Distribution Michael Sullivan testified that in the 15 days up to and including the day of the blast, Shirley’s home consumed 12,800 cubic feet of natural gas, the amount a typical neighbor’s home might use in two months.

“This was definitely out of the ordinary,” he said.

Sullivan estimated it would take 10.65 hours to fill Shirley’s house with that much gas, though if there had been an unsuccessful attempt to destroy the home using a similar method the week before, the amount of gas introduced on the day of the explosion would be less while still achieving the same result.

Prosecutors charge that Leonard and his co-conspirators failed in an earlier attempt to destroy the house with a similar explosion and refined their approach the following week.

Sullivan said that the fuel-to-oxygen mixture would need to remain in the 5-15 percent range to ignite, though that would not necessarily be a uniform level throughout the entire house.

Earlier, Michael Putzek of the Marion County Crime Lab testified that he discovered tool marks on several key pieces of gas meter and fireplace attachments indicating evidence of possible tampering.

Putzek said that while he could not determine if the marks were left the day of the explosion, some showed signs of rust and corrosion indicating they may have dated back to the home’s construction.

Fred Hackett, an independent forensic analyst, testified that a key safety valve on Shirley’s gas fireplace ignitor was missing but the condition of the remaining fireplace debris indicated it was not blown off or destroyed by the explosion.

Jason Burke, a furnace/heating/air conditioning specialist with RT Moore, the firm that installed the original appliances in Shirley’s home at the time of its construction, explained for jurors the variety of safety features common on water heaters and furnaces that would make those devices the unlikely sources of the gas leak and explosion.

Burke also observed a photograph of the manifold attached to Shirley’s gas meter and noted the absence of a Maxitrol regulator which moderates the amount of natural gas piped into the home and could be removed by simple household tools.

“You would never have a legitimate reason to do this as a homeowner,” he said, adding that if the step down regulator were removed, there would be marks left on the pipes.

Burke said during construction or maintenance work, service or installation personnel will often use a tool with a nylon or cloth surface to avoid leaving marks on piping.

Defense Attorney David Shircliff said Burke’s testimony left him much more educated regarding furnace and water heater repair and installation. Then he released the witness without further questions.

After the trial was recessed for the weekend, Shircliff met with reporters to distribute a timetable regarding alleged prosecutorial misconduct in the failure of the State to inform the Defense about the faulty gas flow calculations of Dr. David Sheppard of the Bureau of Alcohol, Tobacco and Firearms (AFT).

“If you noticed, the State withdrew the witness we were asking to exclude that we filed a mistrial about, so we think we made our case,” said Shircliff, claiming a partial victory at a stage in the trial that has seen the Defense file multiple objections, many of which have been overruled by Judge Marnocha. In rejecting the Motion for Mistrial, the Court noted the issue was moot as the Prosecution voluntarily withdrew Sheppard’s testimony and report before it was ever presented to the jury.

Shircliff agreed with a reporter who speculated that the technical testimony of Sullivan, the Citizens Energy engineer, may have been somewhat confusing, but Deputy Prosecutor Denise Robinson disagreed, even though her discredited ATF agent and the results of his calculations computed at the federal agency’s Maryland laboratory were intended to be illustrative and bring even more credibility to the State’s case.

“I don’t think he was talking over their heads,” she said when asked about Sullivan’s testimony. “I think he was pretty clear, and as far as losing one of the key gas people, when we sat down and looked at the evidence we had, you know, the jury will have all the evidence in this case.”

The jurors heard previously from other utility witnesses who testified about utility bills regarding the amount of gas, equivalent to more than three tons of TNT, that could have potentially been introduced into the house that Saturday.

When testimony resumes Monday, IFD and IMPD investigators will begin weaving the threads of the case through its multiple conspirators as well as the planning, attempts and motives for the explosion.

The woman who owned the house at Ground Zero, a divorced mother of a young daughter who attended parochial school, Monserrate Shirley, will make good on her promise to cooperate with investigators by taking the stand against her former lover, explaining that Leonard pressured her into hiking the amount of insurance she carried on her twice-mortgaged home and then conceived of the plot to blow the dwelling literally sky high in pursuit of a fraudulent settlement.

One witness told police Leonard was already shopping on-line for a Ferrari he intended to buy with his proceeds from the scheme.

Instead, he faces life without parole if convicted while Shirley is looking at decades in prison away from her daughter after pleading guilty to reduced charges.

John Shirley testified that after Leonard moved into his former wife’s life, the mother of his child garnished his wages in an attempt to add to her bank account in the wake of a failed bankruptcy and sale of her home, forcing Shirley to work three jobs to raise the cash.

Meanwhile, Leonard was a frequent customer at a number of Indiana casinos and defrauding other women, claim prosecutors, and hatching the insurance fraud plot as his criminal record shown he had done before.

During his testimony, Shirley was seated just feet away from the man who is accused of destroying the home his daughter shared with her mother.

In the courtroom gallery, so was John Longworth, father of Dion Longworth, father-in-law of Jennifer Longworth, the two people next door who died that night.