what can you do in international waters with impunity? who determines a valid flag?

e.g. can you take illegal drugs “openly”?

The question about the flag basically is, what flag is or is not valid? Does it have to be a flag of a real nation? Can you create a micronation with its own aberrant set of laws (perhaps no laws at all )and claim to go under its flag?

Also, what happens if you don’t have any physical flag at all on your vessel?

If I understand my maritime law correctly, you are subject to the laws of a country if you are at their port or in their waters, or failing that, the you are subject to the laws of your flagged vessel’s country.

Whether a flag is allowed or recognized is dependant precisely upon whether or not given countries recognize it. Therefore, making up your own flag doesn’t really work - people do not recognize it. Usually, a flagged vessel must conform to a known set of laws and regulations and be certified as such (although actual enforcement varies).

I am honestly not sure if you even need a physical flag anymore. I think the big ships just use radio signals and painted emblems.

Staff report on this subject: In international waters, are you beyond the reach of the law? - The Straight Dope

Of course. Or do you also think you can make your own passport from Lollipop Kingdom and travel around the world with it?

You can claim that but authorities would just laugh and detain you for any laws you had broken.

Papers are what matter.

You seem to be under the mistaken impression that being under some country’s flag is a hindrance and that you would be freer without that. In fact it is quite the other way around. A flag gives you rights and protections which you otherwise do not have.

Interesting. So as a ship flying no flag, I’m fair game for anyone, including the real nasty ones, whereas if I fly the Canadian flag, I must be dealt with according to Canadian rules.

e.g. suppose somebody get registered with Ghana and has the relevant flag. The Canadian navy, for whatever reason, arrest them in the international waters off Canada for taking drugs. Well, what happens next? Are they airlifted to Ghana to stand trial? Also, probably drugs are illegal in Ghana, but what if it was some other activity that was LEGAL in Ghana but illlegal in Canada?

Did you read the article I linked?

Rather disappointing if I may say so,I have this friend who was rather hoping that I could,that is he could, strip naked in international waters;cover themselves in warm chocolate and beat their own genitlia with opium drenched snow leopards while making obscene comments about Gordon Browns sex life…

But it seems like its just not going to happen.

Lawyers,international or otherwise,are a bunch of irritating spoilsports.

In some countries, this not just legal, it is actually an annual obligation.