Excessive service of alcohol contributed to the drownings of a trainee surgeon and aspiring professional diver on separate nights out, a coroner has ruled.
Melbourne-born Dr Robert Xu drowned in the early hours of November 7, 2019, at the Hobart waterfront after falling from a footpath between two fishing boats.
About three months later, 27-year-old Jarrod Davies died after he fell off a pier in the same area after being assaulted and likely concussed at a bar.
Mr Davies, who was from Victoria, was visiting Tasmania for a maritime health and safety course.
In findings published on Wednesday, coroner Robert Webster said excessive service of alcohol was a cause of both men's deaths.
"(They) died after being served, and after consuming, too much alcohol to the extent that both men were incapable of looking after themselves," he said.
Mr Davies consumed at least 21 drinks, including 10 schooners of beer, over almost 12 hours.
At the Telegraph Hotel on Hobart's waterfront, he bought nine spirit drinks over 72 minutes - two of them for another person.
He then purchased a further 14 drinks at the nearby Observatory Bar.
Mr Webster said Observatory Bar staff were properly qualified and although they believed Mr Davies was not intoxicated when they served him, this was not the case.
"It is clear from the evidence ... that the procedures designed to ensure effective control over the sale and consumption of liquor were not followed," he said.
Mr Davies spent four seconds on the floor of Observatory Bar after being headbutted and punched by a fellow patron but the assault was not seen by staff.
He was escorted from the venue by two crowd controllers.
In a 1.14am phone call with his dad, who he had earlier shared a pub meal with, Mr Davies was slurring his words and "not making any sense".
He fell in the river about three minutes later. His body was recovered by divers two days later.
"(His) level of intoxication was such as to render him incapable of extracting himself from the water," Mr Webster said.
"He was ... a very experienced open water diving instructor and he was a strong swimmer."
A forensic pathologist didn't rule on the official cause of Mr Davies' death, but said it was highly likely accidental drowning while intoxicated.
Dr Xu, described as dedicated and hard-working, was estimated to have had a blood alcohol level of more than 4.5 times the legal limit when he walked off a ledge.
He had been at a dinner as part of a trip for a conference and had at least 10 drinks.
Mr Webster said there was a high likelihood liquor laws weren't followed when Dr Xu was drinking at Evolve Spirits Bar.
He made a handful of recommendations including for random spot checks of licensed premises by authorities for potential alcohol service breaches.
Additional ladders and lifebuoys and signage have been installed at the waterfront since the deaths.