During the sixth court session regarding the sinking of the sightseeing ship 'KAZU I', which resulted in 26 deaths and missing persons off the coast of Shiretoko Peninsula in Japan, a former coast guard officer stated that there was a significant risk of capsizing due to the vessel's construction materials being prone to damage in rough seas. The officer emphasized that if the ship faced strong waves, it could suffer cracks leading to sinking. In response to a question about the likelihood of capsizing had the hatches been closed on the day of the accident, he rated the risk as '7 to 8 out of 10', while noting that a highly experienced captain would have a much lower likelihood of failing to return safely.

The prosecution argued that Seiji Katsurada, the president of Shiretoko Sightseeing Boat who faces charges of professional negligence resulting in death, failed to prevent sailing despite forecasts of inclement weather. Meanwhile, the defense claims that the vessel sank due to an overlooked defect in the hatch on the deck that prevented it from sealing properly, leading to flooding.

In the hearing, a fisherman scheduled to take out a ship on the same day also testified, revealing that after reviewing the previous day's weather forecast, he decided to cancel his fishing trip due to safety concerns regarding possible navigation hazards. This testimony adds weight to the prosecution's case against the operational decisions made on that day, reflecting the overall tensions surrounding the tragedy and the accountability of those managing the vessel's operations.