A government psychiatrist told the District Court yesterday that a former altar boy's alleged sexual abuse at the hands of a former priest may have triggered his schizophrenia. However, Dr Wong Meng-kong, senior medical officer at the Yung Fung Shee Memorial Centre, said the complainant's condition did not necessarily mean his recollection of the events could not be trusted. The former altar boy, now 27, who cannot be named for legal reasons, earlier told the court that former priest Michael Lau Ka-yee, 42, molested him in January 1991 and July 1992 at his dormitory. According to medical reports prepared by Dr Wong, another possible contributor to his patient's mental illness, which first appeared in October 1991, was the death of his father, an ex-civil servant, who died of liver cancer on May 5 that year. Dr Wong said the alleged victim's account of his allegations was clear and consistent, so it was possible the abuse did occur. 'While it is possible that the recollection of past sexual abuse by the priest was delusional, given his clear and consistent recollection of the events and the religious content of his delusions, it is just as possible that the abuse actually occurred and might in fact be the principal precipitating factor of his schizophrenic illness,' Dr Wong quoted from one of his reports. The alleged victim, who was diagnosed with schizophrenia in February 1992 in Britain, has been a patient at the memorial centre since 1992 and has consulted Dr Wong since October 1995. Testifying as an expert witness for the prosecution, Dr Wong said the alleged victim had fully recovered from his mental illness and suffered no memory loss. 'I always felt he was able to distinguish right from wrong,' the doctor said. The prosecution claims that on January 4, 1991, Lau invited the altar boy to his dormitory at St Joseph's Catholic Church and Anglo-Chinese Primary School in Kwun Tong, where Lau molested him under the guise of 'sexual therapy'. Another fondling incident was alleged to have taken place in July 1992, also at Lau's dormitory. Lau has denied three charges of indecent assault, one alternative charge of attempted buggery, and another of gross indecency. Lau resigned from the Church on September 15, 1995, and was arrested in May last year. Judge Maggie Poon Man-kay yesterday ruled that Lau had a case to answer after government lawyer Michael Arthur closed the prosecution's case. The trial continues.