Witness targets analysis of DNA

A DNA expert known nationally for her criticism that led to the temporary shuttering of Houston's crime lab turned a skeptical eye to Bexar County's procedures Tuesday as testimony resumed in the high-profile murder trial of Jon Thomas Ford.

Dr. Elizabeth Johnson described the DNA analysis of a bloody towel found over the head of Dana Clair Edwards, 32, as potentially sloppy.

Ford, 43, was arrested in February 2010 a little more than a year after Edwards, his ex-girlfriend, was found strangled on the floor of her guest bathroom. Her dog Grit was found dead at nearby Olmos Dam a week later.

Ford told police he was home asleep in the first hours of New Year's Day 2009, when the killing is believed to have occurred, but his cellphone records suggest otherwise. The eventual link of Ford's DNA to the towel was one of the major breaks in the case that led to the arrest, authorities have said.

Johnson on Tuesday focused in part on the admission that a Bexar County crime lab analyst found his own DNA in one of eight cuttings he took from the towel. Two other cuttings showed DNA consistent with Ford's.

That's really bad form. ... It's among the most preventable types of contamination, Johnson said. Any time you see an analyst that had a careless event such as this ... you have to wonder how careless and sloppy that person is.

Johnson took the stand at the request of defense attorney Dick DeGuerin, who once represented her in a successful whistle-blower lawsuit against Harris County, where she helped establish a DNA lab in the early 1990s.

Her later criticism of the Houston Police Department's embattled crime lab has been credited, in part, with leading to the facility being shut down in 2002. The lab's DNA division remained shuttered for four years.

But prosecutor Kirsta Melton noted during cross-examination that Johnson, whose consulting business is based out of Southern California, seems to work exclusively for defense attorneys these days.

Ford's DNA was discovered on the towel in December 2009, but his DNA swab obtained by police wasn't tested for comparison until a month later, Melton pointed out. That would make accidental cross-contamination in the lab an impossibility, she suggested.

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Witness targets analysis of DNA