AN investigation into a fatal pleasure boat tragedy, completed yesterday, may lead to charges being brought against the owner. Police will study the report and consider postmortem examinations of the three victims of the Christmas Day accident before deciding whether to press charges. They have privately ruled out the version of events described by the only survivor, Cheng Kit-wai, and do not believe the vessel hit an unlit buoy near Chek Lap Kok. The Marine Department investigation was hampered by the failure to find the powerful seven-metre vessel, which sank north of Lantau Island. Mr Cheng claimed he and his friends were wearing life jackets. But a life jacket was discovered on only one body. 'If they drowned it suggests they were less likely to have been wearing life jackets, although they could have come off,' said a police source. 'The female victim was found with hers not properly fastened.' Alcohol could also have been a factor. The owner and operator of the vessel faces up to four years in prison if found to have endangered lives by compromising safety. Cheng Kwok-wai claimed he sold the boat to one of the victims, Wong Wai-hong, for $60,000, although no change of ownership was registered with the Marine Department. The survivor claims he was not at the wheel. The body of Tang Shuk-kwan, 26, was found 10 hours after the accident, but the bodies of Wong, 21, and Lai Chun-yu, 18, were not found for a week. The inquiry has discovered the boat was speeding outside the main fairway near the Brothers Islands. None of the four was qualified to operate the vessel.