Jim Cunneely stands outside Lenape Valley Regional High School in Stanhope, where he says he had a sexual relationship with his French teacher, Carol D'Annunzio, for more than two years in the early 1990s. (Aristide Economopoulos | NJ Advance Media for NJ.com)

A retired teacher accused of sexually abusing one of her teenage students in the 1990s — an allegation chronicled in a two-part series on NJ.com last year — will not face criminal charges "at this time," a prosecutor said Thursday, adding that the investigation will remain open, though inactive, indefinitely.

Carol D'Annunzio, who taught for more than two decades at Lenape Valley Regional High School in Stanhope, had been the subject of an eight-month investigation by the Sussex County Prosecutor's Office.

The agency opened the probe after inquiries last fall by NJ Advance Media, which reported on one man's transformation from alleged victim of abuse to abuser.

Jim Cunneely, a former French teacher who spent a year in prison for having sex with a 15-year-old student in 2006 and 2007, contends D'Annunzio, his own French teacher in high school, drew him into a controlling sexual relationship that lasted more than two years, beginning when he was 15.

First Assistant Prosecutor Gregory Mueller, who directed the investigation, said that after reviewing the findings, he decided not to bring charges against D'Annunzio, now 65 and living in Wesley Chapel, Fla., just north of Tampa.

"The decision is based on our conclusion that we would not be able to prove the charges beyond a reasonable doubt," Mueller said. "It will remain an open investigation based on the information uncovered during the course of the investigation."

Mueller, no relation to the writer, said the probe will be reactivated if new information is provided to his office. He said the statute of limitations does not apply to the case.

D'Annunzio did not respond to a request for comment after the prosecutor's announcement. She has previously declined to comment.

Carol D'Annunzio, seen here in a yearbook photo, taught French at Lenape Valley Regional High School. She is now retired.

When a reporter visited her home last summer, she was working as a substitute teacher at the Academy at the Lakes, a private K-12 school in Land O' Lakes.

The headmaster, Mark Heller, who was informed of the allegations at the time, said this week D'Annunzio no longer works at the school.

"We have no relationship with her," Heller said, declining further comment.

Cunneely, 39, of Wantage, said he was grateful to the prosecutor's office for conducting what he called a thorough investigation made difficult by the passage of time and a lack of physical evidence.

At the same time, Cunneely said he was disappointed in the outcome.

"I don't want her to serve a prison sentence or lose her pension," he said. "I just want her to take responsibility for what she did. This seems like the last attempt to hold her responsible for her horrible decisions, and that's not going to happen."

Mueller and the lead detective on the case informed Cunneely of the decision in a two-hour meeting Monday. The prosecutor confirmed the meeting took place but declined to recount what was said.

Cunneely said the two men told him some 20 witnesses were interviewed and that investigators had accumulated "a mountain of hearsay evidence pointing to this happening."

"They said, 'We both believe this happened, but what can we prove in a courtroom?'" Cunneely said.

Investigators did not travel to Florida to interview D'Annunzio because they learned she had retained an attorney and that she was not likely to speak with them, Cunneely said Mueller told him.

Of all the letters and items Cunneely said D'Annunzio gave him, he kept only one thing: a crucifix ring she presented during a symbolic wedding ceremony on the banks of the Seine River during a school trip to Paris, he said.

D'Annunzio is seen wearing a similar crucifix ring in several yearbook photos from just before that period.

Carol D'Annunzio in an undated yearbook photo. On her left hand, she is wearing a crucifix ring like the one Jim Cunneely says she gave him during a sexual relationship that lasted more than two years. D'Annunzio is now retired from Lenape Valley Regional High School.

Cunneely said he discarded letters from D'Annunzio when he moved out of his parents' house after college.

That left investigators with little but circumstantial evidence, he said.

In the weeks after the two-day series ran on NJ.com and in The Star-Ledger in November, more than two dozen Lenape Valley graduates contacted NJ Advance Media to support Cunneely's account, saying it was clear to them the two shared more than a typical teacher-student relationship.

"They were always together — before class, in lunch, after class," said Manta Kripotos, who took French with D'Annunzio for four years. "There was no doubt that after sophomore year there was an improper relationship between the two."

Kripotos described D'Annunzio as an "out there, touchy-feely" woman who wore leather miniskirts and who flirted openly with teenage boys.

Another classmate, Brian Havens, said talk of the alleged relationship was so widespread in school that D'Annunzio, then 42, tried to shoot the rumors down, telling him the stories couldn't be true because she was a virgin.

"Nothing ever happened with me, but she was very flirty, and one day after school she told me this creepy virgin story," said Havens, who now lives in Queens. "She told everybody she lived in France, she was going to be a nun, and then she decided she wasn't going to be a nun."

Mueller, the prosecutor, said the investigation was not influenced by the fact that Cunneely pleaded guilty to sexually assaulting one of his own students. Cunneely taught at Kittatinny Regional High School from 2001 to 2007. He is now subject to lifetime parole supervision under Megan's Law.

"Multiple detectives put a lot of time and effort into this investigation," Mueller said. "We took it very seriously."

Mark Mueller may be reached at mmueller@njadvancemedia.com. Follow him on Twitter @MarkJMueller. Find NJ.com on Facebook.

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