Whipkey's body was found May 26, 2002, in a wooded area behind the Westwood Motor Lodge in West Deptford, where Mertz was living. The recent Air Force National Guard enlistee had last been seen about 3 a.m. the day before at the Adelphia Restaurant in Deptford, where she had gone dancing with friends, police said.
Mertz met Whipkey, who had a 4-year-old daughter, outside the club, according to authorities.
He was originally charged with rape and murder. The sexual-assault charges were dismissed for lack of evidence.
Mertz became a murder suspect as a result of his 2005 conviction for cocaine possession. A routine DNA collection revealed a match with DNA found in semen taken from Whipkey's body. He was arrested in December 2008.
Mertz must serve 421/2 years in jail before being eligible for parole, a spokesman for the Gloucester County Prosecutor's Office said Thursday. Prosecutors had asked that he receive life in prison, while his attorney pushed for a lesser sentence, calling Mertz "redeemable."
Contact Jonathan Lai at 856-779-3220, firstname.lastname@example.org, or on Twitter @elaijuh.