Once you're inside another country's territory, be it on the ground or in their airspace, that country's laws are applicable. The fact that the aircraft carries your homecountry's registration doesn't matter a lot in this respect, that only really starts to become important once you're in international airspace. The point made by FlyingStone is more important here, the conditions of carriage as laid down by your airline can be applied to this situation. If he had not complied, you would also have had a reason to remove him as he was not willing to follow the crew's instructions. Also, once you had left the airspace of that particular country, their laws would no longer apply and the passenger would then have had to follow the laws from the state of registration.
Edited to add: The
Tokyo Convention (1963) might be of interest here, but that was put in place to deal with situations where a conflict between various laws would exist, when the location and therefore the applicability of a state's laws would be unclear or for situations in international airspace. If there is no uncertainty about the jurisdiction, there is no need to use that convention.