THE committee which keeps watch on the ICAC is seeking explanations from Commissioner Bertrand de Speville about internal investigations into allegations that an officer was involved in sexual assault and harassment. The Chairman of the ICAC Advisory Committee, Executive Councillor Felice Lieh-Mak, said she thought the time was right to be briefed on the investigation and disciplinary action taken against the officer. His case has been highlighted by sacked Independent Commission Against Corruption deputy operations director Alex Tsui Ka-kit, who yesterday laid a formal complaint to police that his former boss Jim Buckle had perverted the course of justice in his handling of the affair. Ms Lieh-Mak had previously refused to comment on the case, saying it was an internal matter unconnected with Mr Tsui's sudden sacking. But yesterday she said: ''We will try to get some information for a simple understanding of the case but we are not trying to impinge on the internal workings of the ICAC . . . that is not our job. ''We must make it clear that this has nothing to do with the reasons Mr Tsui was dismissed.'' Mr Tsui raised the issue on the night of his sacking last month to back claims of racist double-standards plaguing ICAC management. The committee's terms of reference allow it to advise Governor Chris Patten and Mr de Speville on ''any aspect of corruption'' in Hong Kong and to keep the ICAC's policies under review. While neither Mr Patten nor Mr de Speville have to accept that advice, the terms also call on the committee to draw to the Governor's attention ''any aspect of the work of the commission or any problems encountered by it.'' Mr Tsui said the expatriate had been transferred after molesting several women under his command in the Operations Department over the last three years. The internal investigation started in March this year and Mr Tsui - who as deputy operations director was responsible for internal monitoring - was initially involved. However, it is understood he told police yesterday that he was told by Mr Buckle to keep out of the investigation as he was handling it. The senior officer had served in the same police force as Mr Buckle in Oxfordshire in the United Kingdom. The investigation identified more than 10 victims and witnesses and it is understood it was then handed to the Attorney-General's Chambers where disciplinary action was recommended. The officer involved - in his mid-50s - has been transferred and his contract will not be renewed when it expires in two months. Mr Buckle has described the claims as nonsense and the ICAC yesterday offered an official ''no comment''. Sources said the man involved had served in the ICAC for about 12 years, working initially as a frontline investigator before moving into operation support roles, rising to the rank of Chief Investigator. A former colleague said he was well-known and liked and news of the investigation had surprised many. ''He was very sociable, and frequently arranged functions after work . . . he was a very likeable man.'' The man is married to an expatriate woman and the couple have children. Mr Tsui said last night he was confident that ''justice will be served''. ''There is a serious injustice involved in this matter and the police, being independent and impartial, will look at things objectively.'' Emerging from the Waterfront police station, Mr Tsui said he had laid a complaint against Mr Buckle and it was now ''up to them to investigate''. He added he hoped alleged victims of sexual harassment would testify to support his complaint but said he did not know if they would: ''There are so many ifs and buts in this case.'' Mr Tsui's lawyer Andrew Lam Ping-cheung said police would have to examine the complaint on points of law, the merits of the case and seek a legal opinion. And he added it was impossible to predict how long the legal processes involved in the case would take. ''We may be seeking legal aid,'' Mr Lam said. Meanwhile Mr Tsui said he would have to meet police again but he refused to name a date, claiming he wanted to avoid the ''hassle'' of publicity. Mr Tsui spent more than three hours with the Chief Inspector Paul Mounsey, Assistant Divisional Commander (Crime) of Waterfront Division, but a police spokesman said it was too early to judge what action would be taken.