Concept:
UNCLOS divides maritime areas into zones with different levels of authority. The Contiguous Zone is the belt of water extending up to 24 nautical miles from the baseline, located immediately beyond the territorial sea.
Step 1: Legal limitations on authority.
In the Contiguous Zone, the coastal state does not have absolute sovereignty (unlike in its territorial sea). Its power is limited to specific areas of 'police' or 'administrative' control.
Step 2: The scope of control.
The state can only exercise control to prevent the infringement of its
customs, fiscal, immigration, or sanitary laws within its territory or territorial sea. It cannot, for example, prohibit innocent passage, which is a right guaranteed to all foreign ships (including warships) even in the contiguous zone.
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Authority in Contiguous Zone = Prevention of infringement of specific administrative laws
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Prevent infringement of customs, fiscal, immigration, or sanitary laws.
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