system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If a crime occurs on an airplane, what country's law applies?
gpt
On an international flight, jurisdiction goes to the State of Registry for the aircraft. This means a US plane retains US jurisdiction, even if it's flying from England to Australia. Or an English plane traveling from New York to California., for example, retains English jurisdiction. You can check out the Tokyo Convention for more information.

There are certain limitations. If there is a safety issue aboard the plane, the chain of command is any Air Marshal aboard followed by the pilot followed by the co-pilot, followed by the next place the plane touches ground.