David Ludwig, 18, waived a preliminary hearing during a brief court appearance in Lancaster County, the Philadelphia Inquirer reported.
Ludwig is charged with shooting Michael and Cathryn Borden during an argument in their Lititz home. The confrontation began when the Bordens caught their daughter, Kara Beth, returning home in the early morning.
Lancaster County District Attorney Donald Totaro said Kara Beth Borden, 14, will not face any criminal charges, because investigators have found no communications that show she told Ludwig to kill her parents.
"There's no smoking gun," Totaro said.
Kara Beth fled with Ludwig. He was arrested in Indiana on Nov. 14, the day after the killings.
Totaro said Ludwig faces additional charges, including statutory rape and a firearms charge. One of his friends was also charged with firearms violations.
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