An interesting article about a High Court case. To understand thios post you'll need to read the article (the post is an expanded version of my online comment).
I think the matter here is that only one of three potential legal issues was covered, duty of care. Short answer is the High Court probably got it right in that the publican did exercise his duty of care - he did try to stop the patron driving.
We could perhaps go further in defining the responsibilities of someone legally serving drugs that will result in diminished responsibility. Would the same decision be made if an anaethetist had administered drugs that made a patient drowsy and of impaired judgement and had handed back to the patient the keys knowing the patient planned to drive?
The alternative case may have been a breach of contract, the patron had agreed with the publican to be served alcohol on the condition that the publican retained the keys. I just don't know if enough of the elements of contract exsted in that agreement.
But the really interesting question is that the Court really only ruled that the publican did not have an obligation to not hand over the keys. It did not, contrary to the implication in the article, rule that the publican had to hand over the keys (see note below). That is, the publican may have been safe from the charge of false imprisonment by not handing over the keys, he just didn't have to not hand them over. To take the fire analogy further, while the legal defence of necessity means you can break into a burning house to save a life, it does not oblige you to do so. The pity will be if the judgement results in RSA training being perverted to misrepresent the judgement.
The judgement itself contains a really beautiful summary of the basis for the decision;
The Proprietor and the Licensee must succeed for each of three independent reasons. First, even if there was a duty of care, and even if it was breached, it has not been shown that the breach caused the death. Secondly, even if there was a duty of care, it was not breached. Thirdly, there was no duty of care.
On the more intricate matter of the doctrine of necessity, the judgement said;
The second and third alleged breaches involve the difficulty that deflecting, delaying or stalling Mr Scott, apart from the deception which it would probably require and which itself might have irritated Mr Scott, could not have lasted very long. If it lasted for any length of time, it would have involved non-compliance with Mr Scott's desire to exercise his legal rights to possession of the motorcycle. It would be unlikely, given Mr Scott's mood, that the Licensee could maintain a posture of open non-compliance for long, for a point would soon have been reached at which any manifestation of resistance by the Licensee to returning the motorcycle would involve the actual commission of a tort in refusing possession and would provoke Mr Scott into an attempt to vindicate his rights by self-help. The Licensee could not lawfully detain Mr Scott, or his wife's motorcycle, or the keys to it. Deflecting, delaying or stalling would have been as ineffective as offering counselling to Mrs Cole in Cole v South Tweed Heads Rugby League Football Club Ltd, or persuading her to regain her sobriety in a quiet place before departing from the Club.
I maintain as a non-lawyer that these words don't actually go to the defence of necessity, for the simple reason that it is a defence. That is, breaking into the burning house still includes an unlawful act, trespass. The defence is not that a law was not broken, merely that the breaking of the law was justified. But the fact that it would require a law to be broken does obviate the duty of care, I cannot have an obligation under law to break the law.
As I note it will be a great pity if this part of the judgement is used to prohibit people from refusing to "hand over the keys."