Pre-trial hearing for Gilgo Beach suspect Rex Heuermann remains focused on new type of DNA testing
The legal battle over whether a new type of DNA evidence against accused Gilgo Beach serial killer Rex Heuermann will be thrown out continued on Wednesday.
Heuermann appeared to nod off at times during the hours of complex scientific testimony inside a Riverhead courtroom.
Expert explains concept of DNA sequencing
On the stand was forensic genetics expert Dr. Nicole Novroski, who played a clip from the 1993 film "Jurassic Park" to demonstrate that DNA sequencing is not novel science.
However, the way old, degraded DNA can now be analyzed is new to courtrooms. It could not only impact Heuermann's fate -- he's charged with murdering seven women over two decades, with his DNA allegedly found on tape and belts used on the victims -- it could also set a nationwide precedent.
Whole genome sequencing is used in health care and to exonerate and identify people, but not in murder cases.
"Is this this person's DNA? Are we sure?" said Dr. Julie Burrill, a Stony Brook University DNA forensic researcher.
Burrill explained how it differs from traditional DNA. In layman's terms, even an old low-quality rootless hair strand can now be matched to a suspect if thousands of small locations on the DNA match.
"If you get enough locations and you have enough matching locations between two distinct samples of DNA, that might give you enough statistical weight on that evidence to reasonably infer that these two DNA sources came from the same person," Burrill said.
Defense argues against unproven method
Novroski told the judge nuclear DNA testing is generally accepted in the forensic community. However, Michael Brown, Heuermann's attorney, argued it's unproven.
"This is not science and this should not be accepted in a court of law," Brown said.
The parade of some of the nation's most respected DNA scientists will continue, with the decision ultimately falling to Judge Tim Mazzei, a former prosecutor.
