RIVERHEAD, Long Island (WABC) -- Accused Gilgo Beach serial killer Rex Heuermann appeared in court on Long Island as his defense attorneys formally filed two motions.
Heuermann -- an architect, husband, and father of two from Massapequa Park -- is charged with seven of the at least 10 Gilgo Beach murders.
His attorney on Wednesday filed a motion to sever and to split the seven murders into five separate trials. The defense asked for the first three victims to be in one trial and the remaining four victims to be tried individually.
"When you have count after count, charge after charge, it leads a jury despite a judge's instruction, it leads a jury to say you know what there's so much there," said defense attorney Michael Brown. "He may not be guilty of this but maybe he's guilty of that and it's what we call accumulative effect."
His lawyers also called for the nuclear DNA results from rootless hairs found at six crime scenes to be excluded, claiming they are not generally accepted as reliable in the scientific community, a requirement under state law.
Heuermann's attorney submitted a demand letter for additional evidence and documents involving the DNA testing.
"It's never been the subject of any judicial testing or any standard so this is the first time in the United States that it will be done," said defense attorney Danielle Coysh.
Suffolk County District Attorney Ray Tierney said his office is prepared to defend the DNA technique used by Astrea Forensics, a California laboratory.
"I would submit that this is the next generation of the evolution of the technology," Tierney said. "It's exciting to be at the forefront of that and we look forward to proving the scientific acceptance and effectiveness of this technology."
Tierney has led the charge with the Gilgo Beach Task Force in charging Heuermann.
Last month, Heuermann was charged in the death of Valerie Mack.
A hunter's dog discovered Mack's decapitated body in a wooded area of Manorville on Long Island on Nov. 19, 2000. Her remains were bound with rope inside a black plastic bag which was wrapped with duct tape, court documents said. Both of her hands had been severed from her body and one of her legs was cut off, the document added.
The rest of Mack's remains were found more than a decade later, in April 2011, along Ocean Parkway near Gilgo Beach, authorities said.
Heuermann has pleaded not guilty in the murders of six other women: Melissa Barthelemy, Megan Waterman, Maureen Brainard-Barnes, Amber Costello, Jessica Taylor and Sandra Costilla. The first victim was found in 1993 and the last victims were found in 2010.
His next court hearing is February 18. Judge Timothy Mazzei indicated he would schedule the hearing on the DNA evidence, known as a Frye hearing, for late February or early March.
Heuermann has pleaded not guilty to all charges.
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