The Contiguous Zone

In one line

The contiguous zone is a twenty-four mile belt in which the coastal State may police four things and nothing else.

In the wording a student can write in an exam: under article 33 of the Convention on the Law of the Sea, in a zone contiguous to its territorial sea the coastal State may exercise the control necessary to prevent infringement of its customs, fiscal, immigration or sanitary laws and regulations within its territory or territorial sea, and to punish infringement of those laws committed within its territory or territorial sea. The contiguous zone may not extend beyond twenty-four nautical miles from the baselines from which the breadth of the territorial sea is measured.

Why it exists

The problem it solves is old and practical. A smuggler waits just outside the territorial sea, transfers his cargo to small boats, and runs it in. By the time the goods are inside the territorial sea it is too late to stop them, and outside it the coastal State has no power at all.

So States claimed a further belt in which they could not govern but could police, and the Convention accepted it in a carefully limited form. The zone is an enforcement device and nothing more.

The four purposes

Article 33(1). In a zone contiguous to its territorial sea, described as the contiguous zone, the coastal State may exercise the control necessary to:

(a) prevent infringement of its customs, fiscal, immigration or sanitary laws and regulations within its territory or territorial sea;

(b) punish infringement of the above laws and regulations committed within its territory or territorial sea.

Article 33(2). The contiguous zone may not extend beyond twenty-four nautical miles from the baselines from which the breadth of the territorial sea is measured.

Read that provision slowly, because four limits are packed into it and every one of them is examinable.

Only four subjects. Customs, fiscal, immigration and sanitary. Not fisheries, not security, not the environment, not scientific research. A State that boards a ship in the contiguous zone for a fisheries offence is acting outside article 33, though it may have power under the exclusive economic zone regime instead.

Control, not sovereignty. The article says the coastal State may exercise control. It does not confer sovereignty, and its laws do not apply in the zone as such.

The offence must relate to the territory or territorial sea. This is the limit students most often miss. The zone lets a State prevent an infringement that would occur within its territory or territorial sea, and punish one already committed there. It does not let the State create offences that can be committed in the zone itself.