Natalie Ciappa was due to graduate Plainedge High School last month. She died of a suspected heroin overdose while attending a party at Sung's home in Seaford. Sung, who is 19, has not been charged in the girl's death.
Authorities said last week they charged the girl's ex-boyfriend with participating in a heroin distribution ring.
Sung's attorney, Anthony Grandinette, said his client is being made a scapegoat.
"Mr. Sung played no role in her purchase or use of heroin that evening, which caused her death," he said. "Given these facts this prosecution is both irresponsible and outright cruel."