I went to visit Vietnam with a vietnamese friend (staying at her house while visiting) and while I was there this question popped into my mind.
Normally countries try not to detain people from other countries for political reasons because they could ignite an international incident. But what if said person is a citizen of that country aswell as another? What would happen then? Would the second country have any claim?
Edit: By political reasons I mean stuff like he said something bad about the communist party/leader or something to this end.
If someone had dual citizenship, and they're detained in a country he is a citizen of, unless he's got a particularly high-profile political or business connection with the other country, which is very unlikely, I don't see why the other government would oppose it. Perhaps if the offence itself is political and evidence seems shaky.
Depends on the relations between the two countries, but I know in my UK passport it says that the UK will provide assistance if I get in trouble with the authorities of another nation... unless I am a citizen of that foriegn nation. Might not be the same for every country though.
I have two citizenships, but I've never been detained and I hope I never have to find out.
That said, I can't imagine relations between the U.S and Canada could get bad enough to where one country wouldn't allow me to go to the other...
I would think of it like multi-classing, you take the benefits of it, but also the bad stuff. So if you get imprisoned in one, you're a citizen there and have to go with the flow of that place.