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Three of the four survivors of the Anzac Day boat tragedy that claimed the lives of two young Auckland schoolchildren were drinking on board the vessel - and one had been smoking cannabis earlier that day.
Police confirmed to the Herald on Sunday "alcohol and cannabis were present on the vessel" before it sunk and the inquiry team was investigating whether "any substance played any part in the tragedy".
However, those on board the vessel say they believe neither alcohol nor drugs were factors in the tragedy.
Eight-year-old Erina Rowles and her 5-year-old brother Travis perished when the 7.3m aluminium runabout they were on with their parents, Lindsay and Tania Rowles, and two others sank in calm waters off Tarahiki Island around 2am on Anzac Day.
In today's Herald on Sunday special investigation on the tragedy, two of the four adult survivors, Matt Ironside and James Price, said they and skipper Lindsay Rowles had been drinking on board the vessel before it sank. Ironside also admitted to smoking cannabis earlier in the day.
When questioned a week ago about what extent - if any - alcohol and drugs may have played, police said no conclusions had been drawn on why the boat went down.
Questioned further, police confirmed they were looking at whether or not alcohol and "any substance" were factors in the tragedy. Police also said a scene examination of the boat and seabed near the sunken vessel had turned up "a number of items" of interest to the investigation.
Inquiries into the tragedy were ongoing and no conclusions had been reached about whether anyone on board the vessel would face charges, police said.
Ironside maintained neither alcohol nor drugs were a factor in the boating tragedy.
"I had a $50 bag of weed and I had a smoke before we went out. That's all that needs to be said about that," Ironside said.
He also probably had "a dozen [beers], maybe a little bit more" over the course of the day, while Rowles would have had between six and eight bottles of beer. Price was unsure how much he had consumed, but said it was less than Ironside.
Tania Rowles had not been drinking, the pair said.
Price said there may have been three or four dozen bottles of beer on board the boat, but most had ended up in the sea unopened when the vessel went down.
"Alcohol played no factor in [the tragedy]. There was no way alcohol was affecting Lindsay's judgment.
"He wasn't even slightly drunk," Ironside said.
To date, police have been unwilling to speculate on the cause of the tragedy but have confirmed a bung was missing from the vessel when it was recovered from the ocean floor. Whether that bung had been missing when the boat left Devonport about 11am on April 24 is still unclear.
The runabout has been inspected by a marine surveyor who confirmed he found damage to the vessel, but again was unsure whether that had happened before the actual sinking.
