PULASKI — A medical examiner will not be allowed to testify later this month that she determined Mindy Dickerson’s 2005 death to be caused by asphyxiation, a judge ruled Thursday.

Leslie Dickerson, Mindy Dickerson’s former husband, is charged with first-degree murder in relation to her death. His case is scheduled to be tried by a jury Sept. 22 through Oct. 3.

After the Thursday ruling, one of Leslie Dickerson’s lawyers, Jimmy Turk, said the prosecution should now consider dropping the charge.

Mindy Dickerson was 26 when she was found dead Jan. 27, 2005, in the Pulaski County home she shared with her then husband and young son.

Mindy Dickerson’s death was at first ruled to be caused by encephalitis, or inflammation of the brain. At some point, another medical examiner changed the cause of death to “undetermined.” In 2012, a third medical examiner re-examined what was believed to be Mindy Dickerson’s brain tissue and found that the tissue did not match Mindy Dickerson’s DNA, according to testimony.

Thursday was the third motions hearing in the case in which the main issue discussed has been whether or not tissue samples taken from Mindy Dickerson’s brain stem were too contaminated. The tissue samples were tested three times, and DNA from other individuals was present.

Pulaski County Circuit Court Judge Marcus Long said Thursday that it’s clear “something drastic” happened to the evidence. Because it’s “not the same evidence” anymore, the chain of custody was broken, Long said. When the chain of custody is broken, the evidence is not admissible.

Long ruled to exclude any testimony involving the DNA of Mindy Dickerson. That also includes Amy Tharp’s report on the cause of death because her determination was based “in large part” on the tissue not belonging to Mindy Dickerson, Long said.

The original medical examiner, William Massello, has testified that there is “nothing sterile about the morgue” where autopsies are completed. That’s because there’s no need to worry about infecting a living being, he said.

But, he has said, there is no reason to believe that he was examining anyone but Mindy Dickerson’s tissue. The DNA contamination does not affect the diagnosis of encephalitis, he has said.

The original tissue has been sitting in formaldehyde for years, Massello has said, and the original DNA would probably not be present in significant quantities because of that. Somewhere along the way, other tissue was transferred into the samples, he has said.

Tharp testified that she took tissue from a jar at the medical examiner’s office that was labeled with Mindy Dickerson’s autopsy number. After testing it, she discovered that the tissue was not a DNA match for Mindy Dickerson, whose body was at some point exhumed during the investigation, according to testimony.

Tharp said she could not answer Long’s questions about how other DNA was present, but she said the tissue would have had to have been contaminated, altered or substituted.

She also said that in the past, in unrelated cases, she has had to stop her technicians from putting tissue in the wrong jar.

Also during the hearing, Leslie Dickerson’s lawyers requested from the prosecution any communication that occurred between Tharp and Mindy Dickerson’s family.

Tharp has previously testified that she did not consult anyone while making her determination on cause of death because she did not want to be influenced. Turk said it’s “highly relevant as to what correspondence” she had with family members “based on her assertion that she wanted to remain independent.”

Turk said after the hearing that he has a lot of trust in Pulaski County Commonwealth’s Attorney Mike Fleenor and thinks “Mike will do the right thing.” He said he considers the right thing to be to drop the charge.

Because of Long’s ruling, Massello’s testimony about the cause of death will now be presented to the jury without contradiction, Turk said.

“It’s one of those very, very difficult cases,” Turk said after the hearing. “We’re not trying to pull the wool over anybody’s eyes. All of our witnesses are agents of the commonwealth of Virginia.”

Dickerson was arrested Jan. 14 in Montgomery County, Texas, after he was indicted by a grand jury. He was extradited to Virginia. He remained incarcerated at the New River Valley Regional Jail on Thursday afternoon.

According to her obituary published in The Roanoke Times, Mindy Dickerson was a 1996 graduate of Richlands High School and a 2001 graduate of Radford University.

She was employed by Cingular Corp. at the time of her death.

Leslie Dickerson remarried, and he and his family — including his son from his marriage to Mindy Dickerson — had been living in Texas, according to Leslie Dickerson’s Facebook page, accessed by The Roanoke Times in January.

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