Since the flag state can define the nature of this link, in
practice it can register any ship it chooses. Once
registered, the ship becomes part of the state for legal
purposes. The ‘flag state’ has primary legal responsibility
for the ship in terms of regulating safety, labour laws
and on commercial matters. However the ‘coastal state’
also has limited legal rights over any ship sailing in its
waters.
The rights of the coastal states are defined by dividing
the sea into the ‘zones’ shown in Figure 12.1, each of
which is treated differently from a legal point of view.
The territorial sea (the strip closest to land), the
contiguous zone and the exclusive economic zone. The
fourth zone is the high seas which nobody owns. None
of the zones are precisely defined. Although the 1982
Convention fixes the limit to the territorial sea at 12
miles, Table 12.2 shows that many different limits are
in use. The most common is 12 miles, but a few countries
have adopted much more extensive limits. The
contiguous zone and the exclusive economic zone are
mainly of interest to shipowners because pollution control
and prevention rights are granted to the coastal states in
these areas. These zones are briefly defined in Box 12.1.