If someone commits a crime in Canada, can this person be arrested in USA while being a national of a third country?
4You haven't included a political component of this. As such, Law.SE would be a better place for this question than here. Note that it may matter which third country.– BrythanAug 28, 2016 at 19:06
This process is called Extradition and it requires a treaty.
There is an extradition treaty between the United States and Canada which is in force since 1976.
Each Contracting Party agrees to extradite to the other, in the circumstances and subject to the conditions described in this Treaty, persons found in its territory who have been charged with, or convicted of, any of the offenses covered by Article 2 of this Treaty committed within the territory of the other, or outside thereof under the conditions specified in Article 3(3) of this Treaty.
The treaty does not contain an exception for people who are nationals of a 3rd country. They rarely do. That's why Sweden wants the United Kingdom to extradite an Australian to them, but the Australian doesn't want that because he is afraid he will then be extradited to the United States for unrelated allegations.
Another example: The United States don't have an extradition treaty with Russia, which is why a certain other person accused of committing a crime in the United States feels quite save there.
So basically, if anyone who is national of a country, go living legally in a 2nd country can commit a crime in a 3rd country and come home to 2nd country before being arrested, he's basically safe, right ?– BregaladAug 28, 2016 at 19:25
@Bregalad When the countries 2 and 3 have no extradition treaty and the person is careful to never step into a country which has an extradition treaty with 3, then yes. But when the case has political relevance, there might be diplomatic attempts to convince a state to do an extradition despite lack of a treaty. Also, there is the principle of Aut dedere aut judicare which some states follow for especially severe crimes.– Philipp ♦Aug 28, 2016 at 19:27