Three people were found guilty on corruption charges yesterday in a high-profile bribery case that netted the conviction of Chan Kau-tai, father of Canto-pop star Eason Chan Yick-shun. Witness testimony proved that a trio of building supply executives - Lawrence Yu Chi-wai, 49, Wong Hung-ki, 57, and Ann Wong Tin-sum, 41 - paid off Housing Department officials in a bid to curry favour on coming building projects, Mr Justice Andrew Chan Hing-wai ruled in the District Court. The scheme, which started in the late 1990s, also let the circuit-breaker suppliers charge excessively high prices by keeping rivals out of the market, the court heard. Mr Justice Chan dismissed the defendants' attempts to explain away HK$1.9 million in bribes - hidden through fake purchase orders - as 'absurd' and 'simply unbelievable'. Ann Wong, a financial controller, did not ask questions about the purchase orders because she was aware of their real purpose, the judge said. 'I do not accept her lack of knowledge - she was a financial controller,' he said. 'Either she didn't control anything or was not fit to be in that position.' After a 42-day trial, the three executives were each convicted on two charges of conspiracy to falsify accounts and two charges of conspiracy to offer an advantage to public servants. A sentencing hearing was scheduled for December 18. It was unclear how much money the scheme generated, but the defendants and their companies - Mpower Engineering and ABB Industrial and Building Systems - charged the Housing Department about 40 per cent above private sector rates. Their convictions came two years after Eason Chan's father, the housing department's one-time chief building services engineer, was found guilty on bribery charges and sentenced to six years in prison. His appeal against the sentence on grounds of ill health was denied this year by the Court of Appeal, which said he was lucky not to have received a stiffer sentence. 'It is hard to imagine a more blatant case of public corruption,' the appellate court said. Shum Chiu, another defendant charged in the case, will go on trial in the summer after his case was separated from the trio's trial because he was suffering from cancer. Two other people charged have yet to go on trial, while the three defendants convicted yesterday will be tried again on conspiracy charges stemming from the same case. This week, Mr Justice Chan ruled that anti-corruption investigators acted in good faith when they taped a conversation between Yu and a key prosecution witness at an Italian restaurant. Defence lawyers had argued that the conversation was privileged and could not be used as evidence at trial because a pair of solicitors were present at the meeting. 'There was no abuse of executive power in this case,' the judge said. He declined to disqualify himself from the trial this year amid conflict-of-interest allegations over his previous work on the case when he was in the Department of Justice.