The former educators are being sued in the ACT Supreme Court by 28 men who say they were molested by teachers at the school over three decades.

Documents lodged to the court by lawyers acting for the former educators say they had no ''duty of care'' towards the men when they were students at the Pearce school.

''The defendants deny they owed a non-delegable duty of care to exercise reasonable care for the safety of the plaintiff,'' the documents say.

The Marist order is claiming that it was not responsible for the operation of the school during the time the sexual abuse of the students was taking place and is not liable for damages to the victims.

Former college headmasters and teachers are being sued individually for sexual abuse allegedly inflicted by Brother Kostka Chute on boys at the school from the 1970s to the 1990s, after the Marist Brothers denied liability.

Kostka, who taught at the school between 1976 and 1993, was sentenced in June to a minimum of two years' jail and one year of weekend detention, for molesting six boys between 1985 and 1989.

The civil claims lodged in the Supreme Court allege that Kostka molested students as early as the 1970s, and various headmasters and teachers were aware of such allegations.

The court has granted leave for the alleged victims' claims for compensation to add as defendants former headmasters and teachers at the school, bringing the number of defendants in the case to 22.

Justice Richard Refshauge ordered lawyers acting for the Catholic Insurance Office, which insures Marist College, to provide the names of headmasters at the Pearce school between 1984 and 1994.

The judge ordered the organisation provide the names of members of the Provincial Council of the Marist Brothers' Sydney province between 1984 and 1994.

Among the secondary school headmasters in the 1980s and 1990s were Brother Joseph McMahon, Brother Terence Heinrich, Brother Christopher Wade, all of whom have since moved interstate or overseas.

The victims' lawyer, Jason Parkinson, said yesterday that he was surprised by the tactic.

''If they are saying that they don't have a duty, then who does?'' he said.

''If they collect the school fees and get the government grants then they should take responsibility.''

Five former students are suing Daramalan College in Dickson over abuse allegedly perpetrated by a teacher, John Paul Lyons, who also taught at Marist in the 1970s and 1980s.