In total 27 witnesses were called to testify. Some of them had seen the ship on its fateful voyage and helped authorities to reconstruct the chain of events. In one of the hearings, Jennifer Batten testified that her husband Derek was an experienced and careful yachtsman, had been around boats for 25 years, and that he was acutely aware of the need for safety. He had earned his recreational skipper's ticket and a qualification in marine radio. Every summer they travelled together to Rottnest Island on various motorboats, although "Kaz II" was their first sailboat. After they bought it, the couple took a six-week sailing course and then sailed "Kaz II" around the Whitsundays twice. Apart from a minor problem with a propeller, the trips were without problems. Batten's wife also stated that the original plan was to sail "Kaz II" to Fremantle as a couple, but that Batten was worried that just two people aboard might not be safe. He decided to take his neighbours, brothers Peter and James Tunstead, with him instead. The trip was planned over several months and discussed daily as they plotted routes with the help of a computer. "They allowed themselves six to eight weeks to get back to Fremantle, but because Des and Peter were retired, it didn't really matter how long they took … They didn't want to sail at night for safety [reasons]", Jennifer Batten said, and they planned to stay reasonably close to the shore. Although Batten was taking medications for high cholesterol, mild diabetes, and had suffered a heart attack at age 50, she believed that he was well enough and fit for the journey. Also heard was Graeme Douglas, the previous owner of "Kaz II", who had sold the boat to Batten. He stated the boat was in good condition when it was sold and that he had met the men on the night before they set sail. He also helped the men plan part of their route and was surprised to see that, according to the police, the men had deviated from their planned route that was programmed in their GPS system. Gavin Howland, the skipper of a commercial fishing vessel called the "Jillian", testified that on 16 April 2007, while fishing on a reef off Bowen, he and his crew saw a white yacht with a torn sail drifting sideways between the reefs through a narrow passage, at up to , in north-northeastern direction along with the current. He came within 50 metres of the boat but was unable to spot anyone on board.