The elite Groton School (search) pleaded guilty Monday to failing to report students' sexual abuse complaints to the state.

Groton officials entered the plea on the day the case was scheduled to go to trial. The school was fined $1,250 and avoided a public airing of damaging testimony.

The investigation began in 1999 after the parents of one student told school administrators that he had been sexually assaulted by a group of older male students. Another student later came forward to say that he'd also been abused by fellow students.

State law requires school officials, doctors, clergy and others to alert social services of any suspected abuse. The boarding school was indicted last summer on one charge of failing to file an abuse report. No individuals were charged.

School officials have said they never hid any abuse, and that they reported three allegations to the state in prior years. They said the student in question did not provide enough information to make a report.

"We can only hope that this guilty plea indicates that the school, after six years of equivocation, has finally acknowledged this responsibility to assure that such activities never again occur," the parents of the victim, who was not identified by name in court, said in a statement.

Headmaster Rick Commons (search), in a telephone interview, said: "In this instance, we believe this is the best way to put the matter behind us." He would not comment further.

Groton School, about 40 miles northwest of Boston, was founded in 1884. Among its alumni are President Franklin Delano Roosevelt (search) and McGeorge Bundy, a national security adviser to presidents John F. Kennedy and Lyndon B. Johnson.

The coeducational boarding school has 355 students.

Middlesex District Attorney Martha Coakley said she hoped the case would set an example to others.

"We felt on principle that it was important to draw a line in the sand about the need for reporting," she said. "(But) it's little comfort for the students six years later."