TWO members of a top Catholic secondary school's management team have resigned in a scandal over the expulsion of pupils wrongly accused of being triad members. The announcement came yesterday as the Catholic Diocese's education office told all 130 schools under its management to improve communication between teachers and pupils in an effort to avoid similar confusion. Two of the three-member management board of St Joan of Arc Secondary School in Quarry Bay - former supervisor Father James Wan, and Benedict Ng Leung-chuen - resigned voluntarily. The four new members last week appointed to the board asked the remaining member, principal Shin Chi-lam, to resign. Mr Shin has been on sick leave for a few days and did not attend the management meeting on Thursday night. St Joan of Arc has a reputation for achieving good exam results. Many graduates have become doctors and lawyers or joined other professions. An apology in the diocese's weekly, Sunday Examiner, on January 21 said the school's expulsion of five Form Six students last summer for alleged membership of a triad society had been too severe. A commission appointed by Cardinal John Baptist Wu Cheng-chung found that none of the students was involved in triad activities. But it said they had misbehaved and had caused disturbance to their schoolmates and teachers, and some form of punishment was due. The weekly, which was edited by Father James Wan, had carried an article saying the school's parent-teacher association supported the move to get rid of the ''triad students''. The students are now attending different schools. One of the resigning members, Mr Ng, who is also the principal of Cheung Sha Wan Catholic Secondary School, accepted the investigation results. He said the decision to go was personal and there had not been any pressure exerted on him. ''Resignation is an act of responsibility for the recent happenings at St Joan of Arc and it is an appropriate time to resign, because the management is being reshuffled. ''To resign before the reshuffle would be irresponsible. If I had not resigned, it would be even worse,'' said Mr Ng, without elaborating. The four new members include Father Joseph Mak, the new supervisor, and former pupil Dr Samuel Leung. Another member, assistant to the Episcopal Delegate for Education of the Catholic Education Office, Lawrence Lo Kong-kai, said the new team would improve the operation of the school. Asked if the board would ask Mr Shin to resign as principal as well as a board member, Mr Lo said: ''I think that would be too severe as a punishment for the wrong deeds of the school.'' He said it was too early to decide what they would do if Mr Shin refused to resign as a member of the board of governors. The diocese yesterday also announced the establishment of a four person advisory group to oversee and advise how the school should improve its management. The members include an Education Commission member, Dr Cheng Kai-ming, and the principal of Wah Yan College Kowloon, Norman So Chung-ping. Mr So hoped the group could do something to improve communication among the management, teachers and students in the school.