California State University in Chico suspended a fraternity after members admitted they participated in an adult film.

The national chapter of Phi Kappa Tau (search) also suspended the school chapter and is investigating the taping several months ago by Shane's World (search), an adult film producer known for using college students in its videos. The company generally provides the female porn stars for the films.

Rick Rees, the university's associate director of student activities, said the fraternity's president apologized, admitting that "it was a bad decision."

The school's fraternity system is already under investigation after a student died in February from drinking a large amount of water. The victim allegedly was being hazed by members of a fraternity that had already lost its school affiliation.

Four members of the Chi Tau fraternity have been charged with involuntary manslaughter in the death of Matthew Carrington, and four other members face lesser charges.

University President Paul Zingg (search) told the Los Angeles Times that Carrington's death was "the last straw" and that if the Chico fraternity system was found to be beyond repair, he would shut it down.