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SOUTH BEND, Ind. (June 25, 2015) — An independent forensic scientist told jurors in the Richmond Hill trial of Mark Leonard that the gas fireplace at 8349 Fieldfare Way was likely the location of the excessive natural gas leak that fueled a fatal house explosion in the fall of 2012.

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Fred Hackett of Midwest Forensic Services testified that a key safety valve on a fireplace ignitor was missing and likely removed before the explosion that leveled the home of Monserrate Shirley, damaged 80 neighboring houses, caused $4.4 million in losses and killed two residents.

Hackett said that wood studs supporting the fireplace box were relatively undamaged by the blast making it unlikely that the valve was lost due to the explosion.

Earlier, a South Bend judge turned down a motion filed by Leonard to have his case declared a mistrial based on a flawed analysis of the conditions present the night of fatal explosion in a south side Indianapolis neighborhood.

Attorneys representing the lead Richmond Hill defendant pressed for a “mistrial with prejudice based on prosecutorial misconduct,” because prosecutors delayed telling the Defense that the State had a problem with natural gas flow calculations by a key witness.

The lead prosecutor countered the Defense motion, saying, “I would be hard pressed to even say it’s disingenious. I will say it’s full of lies.”

Deputy Prosecutor Denise Robinson told St. Joseph Superior Judge John Marnocha, before arguments began, that she had decided to drop Dr. David Sheppard of the Bureau of Alcohol, Tobacco and Firearms (ATF) and his testimony from her list of witnesses.

Robinson said in late May she noticed an aberration in Sheppard’s findings regarding the natural gas flow into a Richmond Hill house on November 10, 2012, which led to the fatal blast later that night.

Sheppard’s recalculations narrowed the window of optimum explosive gas levels inside the house, doubling the gas flow rate, but did not change the State’s theory of the blast.

Defense Attorney Diane Black said the revelation during the trial of Sheppard’s faulty findings, if known earlier, would have altered Leonard’s defense strategy, his lawyers’ opening statements and the cross examination of witnesses.

“The case is really rather simple,” said Judge Marnocha. “There was an explosion at 8349 Fieldfare and as a result of the explosion there was property damage, injury and death. I have not heard that there is evidence connecting Mr. Leonard to that explosion as a principal or conspirator.”

That evidence is expected to be revealed next week with the anticipated testimony of Leonard’s former lover Monserrate Shirley.

Judge Marnocha found that the State acted in good faith to raise red flags about Sheppard’s calculation mistakes when they became apparent in the days leading up to the trial and noted that the Defense had access to the same later discredited report in 2013.

The Court determined that Leonard’s presumption of innocence was not put in peril by the miscalculations and that the removal of Sheppard from the State’s list of witnesses rendered the issue moot.

The first witness jurors heard from after the mistrial hearing was Michael Putzek of the Marion County Crime Lab.

Putzek testified that he discovered tool marks on fireplace pipes and natural gas manifold fittings taken from Shirley’s home.

The investigator told the jury that he could not determine when those marks would have been made on the pipes and fittings, though some marks with rust and corrosion would be indicative of assembly.

Not all marks had corrosion or rust.

The State contends that excess gas was introduced into Shirley’s house through the alteration and removal of safety valves.

Prosecutors charge that Bob Leonard, Jr., Mark Leonard’s half-brother, and Gary Thompson, a longtime friend, visited Shirley’s house hours before the blast and set the stage for the explosion.

Leonard and Thompson are yet to come to trial.