By Ian Simpson

(Reuters) - A federal jury on Friday found Rolling Stone magazine liable of defaming a University of Virginia administrator by publishing a story it later retracted about an alleged gang rape at the school.

The decision followed a three-week trial in U.S. District Court in Charlottesville, Virginia, where the administrator, Nicole Eramo, sued the magazine, owner Wenner Media and reporter Sabrina Erdely for $7.9 million. The jury returns on Monday to determine damages in the case.

Erdely was found liable of actual malice, a key element in libel law, in six statements in the November 2014 story, "A Rape on Campus." Rolling Stone and Wenner Media were each found liable of actual malice in three statements, according to court documents.

To prove defamation, it must be shown that a media organization published what it knew to be false, or did so with reckless disregard for the truth.

The magazine had reported that a female student identified only as "Jackie" was raped at a university fraternity in 2012. The story sparked a national debate about sexual assault on U.S. campuses.

The Rolling Stone story resonated with many who saw it as a battle cry against sexual violence on college campuses. That message was undermined as questions arose about Erdely's methods, and the story ultimately collapsed.

Rolling Stone, which admitted that it never sought comment from the seven men accused of the alleged rape, retracted the story in April 2015, and an outside review found the magazine had failed to follow basic journalistic safeguards. It was an embarrassing blow to the pop culture publication, founded by Jann Wenner in 1967.

Campus sexual assault remains a major concern, with some reports estimating that one in five female students will be a victim during their college years.

Eramo, who was then an associate dean of students, accused the magazine of portraying her as the story's villain and as focused on hushing up sexual assault reports. She now works in an administrative role at the almost 200-year-old university, which was founded by Thomas Jefferson and has long ranked as one of the top public universities in the country.

"The jury’s verdict is a complete vindication of Nicole Eramo, and a complete repudiation of Rolling Stone's and Ms. Erdely's false and defamatory article," Eramo's attorney, Libby Locke, said in a statement.

Mark MacDougall, an attorney at New York's Akin Gump Strauss Hauer and Feld law firm, said actual malice did not mean that the defendants had to dislike Eramo or wish her harm.

"When a reporter, an editor or a magazine behave like they don’t care whether what they publish is false, that’s enough to support a finding of actual malice,” MacDougall said in an emailed comment.

In a statement, Rolling Stone spokeswoman Kathryn Brenner said: "We deeply regret these missteps and sincerely apologize to anyone hurt by them, including Ms. Eramo."

(Reporting by Ian Simpson in Washington, additional reporting by Alex Dobuzinskis in Los Angeles; Editing by Scott Malone, Mary Milliken and Leslie Adler)