Internal waters

The coastal state is free to make laws relating to its internal waters, regulate any use, and use any resource.

When a foreign vessel is authorized to enter inland waters, it is subject to the laws of the coastal state, with one exception: the crew of the ship is subject to the law of the flag state.

This extends to labor conditions as well as to crimes committed on board the ship, even if docked at a port.

The coastal state can intervene in ship affairs when the master of the vessel requires intervention of the local authorities, when there is danger to the peace and security of the coastal state, or to enforce customs rules.

For example, Canada claims a section of the Northwest Passage as part of its internal waters, fully under Canadian jurisdiction,[3] a claim which has been disputed by the United States and most maritime nations, which consider them to be an international strait, which means that foreign vessels have a right of transit passage.