Defense expert offers different DNA scenario

— An expert witness who admits never conducting any mitochondrial DNA tests was called by the defense in the Christopher Porco murder trial to refute the prosecution's DNA expert regarding a toll ticket allegedly linking the defendant to the vicious attacks against his mother and father.

Jurors rubbed their noses, scratched their hair, stretched and yawned as the ambiguous battle to refute the prosecution's findings of the DNA toll ticket continued.

SUNY Syracuse College of Environmental Sciences Biology Professor William Shields said Dr. Terry Melton did not use proper data when coming to a conclusion that there was a 99.61 percent statistical chance the DNA on a thruway toll ticket matched Porco's DNA.

Dr. Melton used a composite database and not a Caucasian data base, said Shields, who believes that because of that error, the tested DNA sample could possibly match 70 percent of the people in the FBI's database, not .039 percent as Dr. Melton testified. DNA experts used an FBI database of 4,839 samples from all races in North America to test their base profile with a composite list.

"Her (Dr. Terry Melton) application of the guidelines resulted in an error, and the FBI makes the same error," said Shields.

Prosecutor Michael McDermott read off Professor Shields' unusual resume that states that Shields is a zoologist, ornithologist and researcher of barn swallows and wild turkeys, even writing a published paper entitled "All men are potential rapists," but not a forensic scientist in the study of DNA.

"Doctor, you never worked in a crime lab," McDermott said.

"Correct," said Shields.

"You never extracted DNA in humans for a mitochondrial DNA analysis," McDermott continued.

"Not in humans, wolves only," said Shield.

"Is it true you never analyzed any piece of evidence that came from a crime scene?" asked McDermott.

Shields said he once analyzed caviar for a case.

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