Melton said she could not. Kindlon asked if Melton could positively state that the DNA on the toll ticket was Christopher Porco's.
"We cannot say for sure that the DNA on that toll ticket is Mr. Porco's," said Melton. "We just cannot exclude him."
Jurors and courtroom observers received a 30-minute primer on mitochondria DNA and its use in population genetics and in the study of evolution from the prosecution's expert witness.
Melton's most famous case as a graduate student was to determine if a woman who claimed she survived the 1918 Bolshevik revolution was indeed the grand duchess and daughter of Nicholas II Anastasia.
"I tested her hair after she died," said Melton. "It was a very exciting case, and I was able to show she was not Anastasia."
That research did not stop Kindlon from continuing his hard line of questioning of the prosecution's DNA expert witness to show jurors the findings are nothing but pure speculation. At one point, Kindlon and Melton spent close to 15 minutes discussing scientific findings and referencing them through a series of several digit numbers that had courtroom observers confused.
"I am going to object to any more testimony from this witness," said Kindlon.
Judge Jeffrey Berry, who is presiding over the Porco murder trial in Orange County Court, denied the motion.
Kindlon reminded jurors that when she tested one of the samples she had no idea it belonged to the murder suspect.
"In fact, you have never seen Christopher Porco before this trial," stated Kindlon.
The defense pressure to crumble a crucial piece of potential physical evidence linking the suspect to the crime continued through the late afternoon hours when Kindlon cited examples of casework contamination in the company's Pennsylvania lab.
"In September 2003, there was a contamination of a casework sample by your technician in your lab," Kindlon said. He added that Melton herself did not perform the test on the Porco toll ticket.