Richard Bilodeau, 63, was arraigned on murder charges for the Nov. 10, 1984, cold-case slaying of Theresa Fusco, thanks to high-tech DNA testing by the FBI, authorities said.

“The DNA was taken from a vaginal swab,” Nassau County Assistant District Attorney Jared Rosenblatt said in court. “The defendant worked the overnight shift at Walmart in Suffolk County.

“When questioned, the defendant denied knowing her,” Rosenblatt told Judge Helene Gugerty. “He denied recognizing the pictures of her. When told about when the crime occurred, [he said], ‘Yeah, people got away with murder back then.”

Fusco, an aspiring dancer, left her job at the popular Hot Skates skating rink in Lynbrook on Nov. 10, 1984, and disappeared — and was found dead and naked nearby on Dec. 5.

Police said the bubbly teen had been raped, beaten and strangled, then dumped in the woods.

The grisly case horrified the quiet suburban community for months, until three local men — John Restivo, Dennis Halstead and John Kogut — were arrested and convicted in the teen’s horrific murder in 1986.

However, DNA evidence later cleared all three after they had served up to 18 years behind bars. They were freed in 2003, then sued and were awarded $43 million for wrongful prosecution, with the verdict later upheld on appeal.

Defense attorney Daniel Russo denied his client was behind the grisly murder.

The charges bring long-awaited relief for the tragic teen’s parents.

On Wednesday, her father, Thomas Fusco, hugged a relative at the courthouse and whispered in her ear, “Now you go home and enjoy the rest of your life. Enjoy your daughter.”

Bilodeau was ordered held without bail pending a return court appearance on Nov. 21.