Serving alcohol on river boats

Hi all. Sorry if this is the wrong section, but here goes.

I am curious as to what the laws are (if any) that cover serving alcohol to the public on river boats. Someone told me that a licence is not required once the boat has cast off and is a certain distance from shore. I have searched and can't find a definitive answer.

TIA.

Mightent be 100% legal but who the hell is going to give out to you out there?

If the vessel is closer to the irish coast than 12 miles (baselines act) then it is subject to irish law. So i the case of a river it would appear that a licence to sell alcohol would be required where it is serving the public.