Milford Public Schools asked a judge Monday to throw out a multimillion-dollar lawsuit in the death of Maren Sanchez, who a classmate stabbed to death several years ago at Jonathan Law High School on the day of junior prom.

Chris Plaskon, whom Sanchez had rejected as a prom date, is serving a 25-year prison sentence after pleading no contest.

Lawyers for Sanchez's family say the school had a chance to intervene six months before the slaying when it received information that Plaskon was potentially suicidal. 

In sworn depositions, school leaders admitted that they didn't follow up. 

"People in the courtroom heard it today, but the people in Milford don't know that there was a mandatory policy that was designed to protect, not just Christopher Plaskon from himself, but others in the school," said David Golub, a lawyer for Sanchez's mother. "Everyone admits it was triggered, and everyone admits it was violated."

James Tallberg, an attorney for the City of Milford, disputed that argument.

"We don't expect our students to murder each other without warning, as occurred in this case," he said.

Lawyers for the district say they did follow up to make sure Plaskon was getting therapy. And they say much of the currently available information about Plaskon surfaced after the slaying.

"How are school authorities supposed to anticipate that?" Tallberg asked. "Six months after Chris expressed some kind of suicidal ideation, how is anybody supposed to predict that he would commit murder."

The judge gave both sides until September to try and reach a settlement.