I recently vacationed in beautiful Montego Bay, Jamaica and the issue that came up was:
What laws do I, as a U.S. citizen, have to follow?
The focus really is on jurisdiction. Jurisdiction is the “legal power” over someone or something. There are essentially three types of jurisdiction you would need to be aware of when traveling abroad.
First, territorial jurisdiction.
While I was in Jamaica, Jamaica has jurisdiction over me because I am physically present inside its territory and must abide by the laws of the country I am in.
Remember Amanda Knox? She was accused of murder in Italy and she was tried under the Italian laws – not American.
Second, is nationality jurisdiction.
The United States can maintain jurisdiction over me even while I am abroad but the general rule is that the law must specifically state that this is the case.
For example, US citizens even living abroad must pay taxes. You never ever escape the taxman.
And a subcategory of nationality jurisdiction, and the least known, is where the crime affects an interest in the U.S. which the law specifically seeks to stop. For example, you cannot set up a money laundering business here in Jamaica and then send the laundered money back to the States. You would still be breaking U.S. law.
However, you can drink at age 18 or even 16, if the foreign country allows, because the safety of U.S. roads is not effected one way or another by what you drink in Jamaica. So you can drink and drive and get into a car accident in Jamaica and the U.S. laws would not apply.
So in conclusion, I have to follow Jamaican laws, the few laws specific to me as a US citizen traveling abroad and any U.S. laws that would effect a significant U.S. interest if broken (mainly financial laws).
Side note – visit Jamaica when you can. It’s beautiful.