A third lawsuit filed against Shattuck-St. Mary's accuses officials at the boarding school in Faribault, Minn., of failing to protect students from a teacher after hearing reports of his sex games and abuse.

The suit, filed Tuesday in Rice County, claims that Lynn P. Seibel — a former drama teacher and "dorm parent" — sexually abused the unnamed plaintiff from 2000 to 2001.

Seibel, 72, pleaded guilty in July to seven criminal, felony counts for molesting six male students between 1999 and 2003. In October 2013, he was sentenced to 52 months in prison.

This week's lawsuit, filed in Rice County District Court by Jeff Anderson and Associates, accuses the school of negligence, negligent supervision and negligent retention and asks for more than $50,000 in damages. Two similar suits filed by the St. Paul-based firm in 2013 were moved to federal court and remain active.

"We continue to stand with anyone who may have suffered from Mr. Seibel's abusive behavior," the school said in a statement, "but the suggestion that we knew of Mr. Seibel's misconduct and did nothing in response is false and unfounded."

According to the criminal charges, Seibel held "naked dance parties," showed students pornography and led group masturbation sessions with underage boys. He sexually abused students after locking the doors to a classroom next to the gym. He would sometimes touch and measure the teens' penises.

The newest lawsuit offers "more facts about what they knew and when they knew it," said Sarah Odegaard, an attorney with Jeff Anderson and Associates.

The lawsuit claims that during the 1999-2000 school year, a Shattuck-St. Mary's staff member "received a report of a situation involving Seibel acting sexually inappropriate with students," but the school "did nothing." Another teacher witnessed one of Seibel's "naked dance parties" in the dorm showers in 2000 and reported it to administrators, the lawsuit says. It also claims that before graduating in 2002, a student reported to the headmaster that he was sexually abused by Seibel. But once again, the school did nothing, the suit says.

After more than a decade at the school, Seibel resigned in 2003 after being caught with child pornography on his computer.

The adult plaintiff identified as Doe AB, said in a news release that he "loved" his time at Shattuck-St. Mary's. "Because the school is so important to me," he said, "I'm bringing this lawsuit to make sure Shattuck-St. Mary's is doing everything that it can to protect students and make sure what happened to me never happens to another student."

In its statement, Shattuck-St. Mary's said the school assisted the police in their investigation. "We place the highest possible priority on the underlying issue of creating and maintaining a safe environment for our students, faculty and staff," the statement says.

Jenna Ross • 612-673-7168