A 1998 MIT graduate who had his diploma suspended this summer for involvement with the death of a first-year fraternity pledge sued the university Tuesday for breach of contract and intentional infliction of emotional distress.

Charles H. Yoo was pledge leader for the Phi Gamma Delta fraternity in September 1997 when Scott Krueger, a freshman pledge, died of alcohol-poisoning at a fraternity party.

More than a year after his graduation, MIT charged Yoo with hazing and violating the school's fraternity policy. MIT's Committee on Discipline voted in August to revoke Yoo's diploma for five years.

Yoo denies hazing Krueger.

"We didn't want a tragedy to occur. We just wanted to create an event that was fun for everyone in the house," Yoo said yesterday.

The Committee on Discipline's rules and regulations states that MIT can withdraw academic degrees after graduation "for actions that occurred before graduation but were unknown at that time."

Yoo's attorney, Timothy M. Burke, charged MIT with violating its own policies by suspending Yoo after he graduated. Burke said the college was aware of the death and criminal investigation while Yoo was still a student.

"Obviously MIT was fully aware of the ongoing investigations being conducted by the District Attorney's office because MIT was a target of the investigation," Burke said.