250

              SEPARATE OPINION OF JUDGE ROBINSON

   1. An interesting and not esoteric question has been raised in this case.
It was not necessary for the Court to pronounce on it in explicit terms.
However, the question may have implications for the functioning of what
the Preamble to the United Nations Convention on the Law of the Sea
(hereinafter “the UNCLOS” or “the Convention”) calls “a legal order for
the seas and oceans” 1, the establishment of which was the primary goal of
the Convention.
   2. Nicaragua argued that there is a “convergence in maritime delimita-
tion methodology” 2 in respect of the territorial sea, the exclusive eco-
nomic zone (hereinafter the “EEZ”) and the continental shelf. In eﬀect,
Nicaragua espouses an approach whereby the principles set out in Arti-
cles 74 and 83 of the Convention, for the delimitation of the EEZ and
continental shelf would apply equally to delimitation of the territorial sea
under Article 15 of the Convention. Indeed, Costa Rica argued that the
eﬀect of Nicaragua’s submission on this point is that delimitation of the
territorial sea under Article 15 of the Convention “must be undertaken in
such a manner as not to prevent or undermine the achievement of an
equitable solution to the delimitation of the EEZ and continental shelf
under Articles 74 and 83” 3. I understand Nicaragua’s submission to
mean that the law under the UNCLOS calls for a convergence in mari-
time delimitation methodology.

   3. This opinion argues that there is no such convergence for the three
zones, although, it is possible for States by agreement to use a single
methodology for all three zones. The opinion maintains that a proper
interpretation of the Convention shows that it calls for a dichotomous
approach, whereby the territorial sea is delimited on the basis of the
median line/special circumstances approach and the EEZ and continental
shelf are delimited on the basis of any method that would result in an
equitable solution.
   4. The decision to convene the Third United Nations Conference on
the Law of the Sea was, in part, a response to the claims of many coun-
tries, in particular developing countries from Latin America, Asia and
Africa, to an extensive zone of jurisdiction beyond the territorial sea. The
precise nature of this zone, which came to be called the exclusive eco-

  1   Preamble, United Nations Convention on the Law of the Sea of 10 December 1982.
  2   CR 2017/11 (Lowe), p. 12, para. 15.
  3   CR 2017/07 (Ugalde), p. 23, para. 16.

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251 maritime delimitation and land boundary (sep. op. robinson)

nomic zone, (although in Latin America it was originally called the patri-
monial sea) was among the most diﬃcult issues faced by the Conference,
and the issue of delimitation of the EEZ between neighbouring States was
perhaps the most intractable problem in the Conference. In 1980, six years
after the Conference commenced and just two years before it concluded,
no agreement had been reached on the delimitation of the EEZ and con-
tinental shelf. There was however, at that time, broad agreement on the
régime for the delimitation of the territorial sea, which generally followed
Article 12 (1) of the 1958 Geneva Convention on the Territorial Sea and
Contiguous Zone.
   5. It will be recalled that the equidistance/special circumstances rule 4
in the 1958 Convention on the Territorial Sea and Contiguous Zone,
which was employed for the delimitation of the territorial sea, also applied
to the delimitation of the continental shelf under the 1958 Convention on
the Continental Shelf. However, UNCLOS’ drafting history 5 shows that,
owing to the potential for natural geographical overlap between the con-
tinental shelf and the newly created EEZ, the provisions for delimitation
of the continental shelf moved closer to those for the delimitation of the
EEZ, the two sets of provisions becoming congruent with each other to
the extent that Articles 74 and 83 have identical formulations. No doubt
this congruence is one explanation for the practice that has developed of
a single maritime boundary being used to delimit these two zones.
   6. During the Conference, States exhibited a preference for equity to
play a greater role in the delimitation of maritime boundaries as one
moved further seaward. An explanation for this preference is that the
potential distorting eﬀects of the equidistance line are more magniﬁed in
the more distant EEZ and continental shelf than in the territorial sea. In
the North Sea Continental Shelf cases 6, the Court said that the distorting
eﬀect of equidistance lines are “comparatively small within the limits of
territorial waters, but produce their maximum eﬀect in the localities
where the continental shelf areas lie further out”. 7
   7. During the Conference, some countries favoured the use of the
median line in the delimitation of the EEZ; others, taking their cue from
the North Sea Continental Shelf cases, favoured the use of equitable prin-
ciples. Obviously any framework for delimitation of the EEZ had to take
account of the diﬀerences between the legal régime of the territorial sea

   4  See Article 6 (1) of the 1958 Convention on the Continental Shelf and Article 12 (1)
of the 1958 Convention on the Territorial Sea and Contiguous Zone.
    5 See generally, Satya N. Nandan and Shabtai Rosenne (eds.), United Nations Conven-

tion on the Law of the Sea 1982: A Commentary, Vol. II, Martinus Nijhoﬀ Publishers, 1985,
pp. 132-143, pp. 796-821 and pp. 948-962; Third United Nations Conference on the Law
of the Sea, Official Records, Vol. XIII, (Summary Records, Plenary, General Committee,
First and Third Committees, as well as Documents of the Conference, Ninth Session),
A/CONF.62/SR.126, 126th Plenary Meeting (1980).
    6 North Sea Continental Shelf (Federal Republic of Germany/Denmark; Federal Repu-

blic of Germany/Netherlands), Judgment, I.C.J. Reports 1969, p. 3.
    7 Ibid., p. 37, para. 59.

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252 maritime delimitation and land boundary (sep. op. robinson)

and that of the EEZ, described in Article 55 of the Convention as “an
area beyond and adjacent to the territorial sea”. For some States, includ-
ing the strongest supporters of an extensive maritime zone of jurisdiction
for the coastal State, the rights of the coastal State in that zone should be
emphasized, while for others, the high seas freedoms of all States in the
zone should receive maximum protection. Articles 56 and 58 of the
Convention reﬂect the compromise that was reached between both groups
of States.

   8. This tug between States was reﬂected in a proposal by Venezuela in
1980 that the concept of equity should govern delimitation in the territo-
rial sea, EEZ and continental shelf 8. In the result, that approach was not
accepted. Article 15 of the Convention reads as follows:

         “Where the coasts of two States are opposite or adjacent to each
      other, neither of the two States is entitled, failing agreement between
      them to the contrary, to extend its territorial sea beyond the median
      line every point of which is equidistant from the nearest points on the
      baselines from which the breadth of the territorial seas of each of the
      two States is measured. The above provision does not apply, however,
      where it is necessary by reason of historic title or other special cir-
      cumstances to delimit the territorial seas of the two States in a way
      which is at variance therewith.”
  Articles 74 and 83 of the Convention read as follows:
         “The delimitation of the exclusive economic zone [continental shelf]
      between States with opposite or adjacent coasts shall be eﬀected by
      agreement on the basis of international law, as referred to in Arti-
      cle 38 of the Statute of the International Court of Justice, in order to
      achieve an equitable solution.”
   9. The main diﬀerence between the legal régime of the territorial sea
and that of the EEZ is that whereas, in accordance with Article 2 (1) of
the Convention “[t]he sovereignty of a coastal State extends . . . to . . . the
‘territorial sea’”, in the EEZ the coastal State only has, in accordance
with Article 56 (1), sovereign rights and jurisdiction in respect of certain
functions. Moreover, Article 56 (2) provides that a coastal State in carry-
ing out its functions in the EEZ, “shall have due regard to the rights and
duties of other States and shall act in a manner compatible with the pro-
visions of this Convention”.
   10. In the territorial sea, therefore, the rights of the coastal State, based
as they are on that State’s sovereignty, are clearly diﬀerent from the sov-
  8 Third United Nations Conference on the Law of the Sea, Official Records, Vol. XIII
(Summary Records, Plenary, General Committee, First and Third Committees, as well
as Documents of the Conference, Ninth Session), A/CONF.62/SR.126, 126th Plenary
Meeting (1980), paras. 137 (statements by Venezuela) and 88 (statement by Argentina).

117

253 maritime delimitation and land boundary (sep. op. robinson)

ereign but functional rights and jurisdiction that the coastal State enjoys
in the EEZ. The rights of the coastal State receive their greatest recogni-
tion and deference in the territorial sea. This diﬀerence between the ter-
ritorial sea and the EEZ is reﬂected in the drafting of Article 15 on the
one hand, and that of Articles 74 and 83 on the other. While Article 15
prescribes a speciﬁc methodology of delimitation, the median line/special
circumstances method, Articles 74 and 83 do not prescribe a particular
method, but point to the achievement of an equitable solution as the goal
of the delimitation. Over the years the equidistance/relevant circum-
stances method, which has evolved through this Court’s judicial interpre-
tation of Articles 74 and 83, has become applicable for delimitation of the
EEZ and continental shelf. In any event, as a practical matter, delimita-
tion — whether of the territorial sea or the EEZ and continental shelf —
begins with a provisional median/equidistance line. The diﬀerent methods
of delimiting the various zones derive from the diﬀerences in their legal
régimes. Another distinction between the two régimes is that Articles 74
and 83 have an explicit reference not only to the dispute settlement pro-
cedures in Part XV of the Convention, but also directs the parties in the
interim period, pending agreement on delimitation, to conduct themselves
in a manner that would not jeopardize or hamper the reaching of a ﬁnal
agreement. This indicates a greater sensitivity to the potential for disputes
on a provision which does not identify a speciﬁc method, but places its
focus on the search for an equitable solution.

   11. The ﬁrst rule of interpretation is that “[a] treaty shall be interpreted
in good faith in accordance with the ordinary meaning to be given to the
terms of the treaty in their context and in the light of its object and
purpose” 9. A plain reading of the relevant articles shows that Article 15
sets out more deﬁnitive and objective criteria for the delimitation of the
territorial sea than do Articles 74 and 83 for the delimitation of the EEZ
and continental shelf. Article 15 requires that if States cannot agree on
the delimitation of their territorial sea, absent special circumstances, “nei-
ther of the two States is entitled . . . to extend its territorial sea beyond the
median line every point of which is equidistant from the nearest points on
the baselines from which the breadth of the territorial seas of each of the
two States is measured” 10. Thus, a departure from the median line is
envisaged only in situations where “special circumstances” exist. Arti-
cle 15, by prescribing the method for delimitation, identiﬁes the median
line as the speciﬁc basis for delimitation of the territorial sea. In Guyana/
Suriname 11, the Tribunal aﬃrmed the primacy of the median line in the

   9 Article 31, Vienna Convention on the Law of Treaties of 23 May 1969.
   10  Article 15, United Nations Convention on the Law of the Sea of 10 December 1982.
   11 Award in the Arbitration regarding the Delimitation of the Maritime Boundary between

Guyana and Suriname, Award of 17 September 2007, United Nations, Reports of Interna-
tional Arbitral Awards (RIAA), Vol. XXX (Part One), p. 93, para. 296.

118

254 maritime delimitation and land boundary (sep. op. robinson)

delimitation of the territorial sea. On the other hand, Articles 74 and 83
are wholly result-oriented; no speciﬁc method is identiﬁed, although in
practice, the judicially developed equidistance line/relevant circumstances
approach prevails. After the Black Sea case 12 (described in more detail in
paragraph 16), one must add to that approach, the element of dispropor-
tionality.

   12. The explicit reference to the median line as a method to delimit the
territorial sea in Article 15 can be contrasted with the silence of Arti-
cles 74 and 83 on the method of delimitation. Absent special circum-
stances, the elements of predictability and certainty resulting from the
requirement to employ the more objective criterion of the median line in
the territorial sea are not present in the delimitation of the EEZ and con-
tinental shelf, which may be seen as oﬀering greater ﬂexibility in method-
ology, the aim of which is to ﬁnd an equitable solution.
   13. Given the diﬀerences between the legal régime of the territorial sea
and that of the EEZ and continental shelf, an interpretation of the Con-
vention, as requiring a single method for delimiting all three zones would
indeed be diﬃcult to understand. This is so because a single method may
not reﬂect, or reﬂect suﬃciently, the varying rights of the coastal State in
the territorial sea on the one hand, and in the EEZ and continental shelf
on the other.

 14. The Court also commented on this diﬀerence in the Nicaragua v.
Honduras 13 case when it stated that,
         “The methods governing territorial sea delimitations have needed
      to be, and are, more clearly articulated in international law than those
      used for the other, more functional maritime areas. Article 15 of
      UNCLOS, like Article 12, paragraph 1, of the 1958 Convention on
      the Territorial Sea and Contiguous Zone before it, refers speciﬁcally
      and expressly to the equidistance/special circumstances approach for
      delimiting the territorial sea.” (Emphasis added.)

This unequivocal statement of what the Court obviously sees as an
imperative requirement to have more clearly articulated delimitation meth-
ods for the territorial sea than in the EEZ and continental shelf is a telling
judicial comment supporting the need for a dichotomous approach. The
dictum means that there is something in the territorial sea, or more speciﬁ-
cally, in the nature of the territorial sea that calls for greater clarity in the
methods for delimiting that zone — that “something” is the territorial

   12 Maritime Delimitation in the Black Sea (Romania v. Ukraine), Judgment,

I.C.J. Reports 2009, p. 61.
   13 Territorial and Maritime Dispute between Nicaragua and Honduras in the Caribbean

Sea (Nicaragua v. Honduras), Judgment, I.C.J. Reports 2007 (II), p. 740, para. 269.

119

255 maritime delimitation and land boundary (sep. op. robinson)

rights enjoyed by the coastal State in the territorial sea. The basis of that
analysis by the Court must be the marked diﬀerence in the legal régime of
the various zones. For it is this diﬀerence that will generally call for diﬀer-
ent methodologies if the basic law governing the zones is not to be contro-
verted. Thus, the provisional median line in the territorial sea has a diﬀerent
value from the provisional median line in the EEZ and continental shelf,
and while special circumstances and relevant circumstances are both modi-
ﬁers, they too, will have diﬀerent values. This was one of the reasons why
the Arbitral Tribunal in Bangladesh/Myanmar 14 in delimiting the territorial
sea gave full eﬀect to St. Martin’s Island, a Bangladeshi island, even though
it is located on Myanmar’s side of the equidistance line, but gave it no
eﬀect in the EEZ and continental shelf. Another example comes from the
instant case in which the Court refused to modify the median line on
account of the Santa Elena peninsula, giving it full eﬀect in the territorial
sea. But the peninsula was given half-eﬀect in the EEZ and continen-
tal shelf.

   15. However, since under Articles 74 and 83 it is open to States to
choose any method for delimitation (in order to arrive at an equitable
solution) and under Article 15, States may agree not to use the median
line, it is possible for States under UNCLOS to agree to utilize a uniform
methodology for delimiting the three zones. In Ghana/Côte d’Ivoire 15, a
Special Chamber of the ITLOS, although acknowledging that diﬀerent
rules apply to the delimitation of the territorial sea and the EEZ, having
heard the submissions of the parties, determined that there was an implicit
agreement that a single methodology should be used for the various
zones.
   16. The Court’s case law as well as the decisions of arbitral tribunals
have consistently followed a dichotomous approach to the delimitation of
the territorial sea and the delimitation of the EEZ and continental shelf.
When the ICJ cases are carefully examined, it will be found that the Court
has never applied a single delimitation methodology for all three zones.
(I do not consider Nicaragua v. Honduras 16 to be a case in which the
Court applied a single methodology, since the Court used the angle-
bisector method for drawing of the single maritime boundary and the equi-
distance method to delimit the overlapping territorial seas generated by
   14 Delimitation of the Maritime Boundary between Bangladesh and Myanmar in the Bay
of Bengal (Bangladesh/Myanmar), Judgment, ITLOS Reports 2012, p. 47, para. 152; p. 86,
paras. 316-319.
   15 Dispute concerning Delimitation of the Maritime Boundary between Ghana and Côte

d’Ivoire in the Atlantic Ocean (Ghana/Côte d’Ivoire), ITLOS Case No. 23, judgment of
23 September 2017, p. 78, paras. 259-260.
   16 Supra note 13, I.C.J. Reports 2007 (II), p. 746, para. 286; p. 752, paras. 304-305.

120

256 maritime delimitation and land boundary (sep. op. robinson)

some islands situated in the territorial sea.) Cameroon v. Nigeria 17 does
not indicate otherwise. It will be recalled that, in Cameroon v. Nigeria,
this Court had said,
         “The Court has on various occasions made it clear what the appli-
       cable criteria, principles and rules of delimitation are when a line
       covering several zones of coincident jurisdictions is to be determined.
       They are expressed in the so-called equitable principles/relevant cir-
       cumstances method. This method, which is very similar to the equi-
       distance/special circumstances method applicable in delimitation of
       the territorial sea, involves ﬁrst drawing an equidistance line, then
       considering whether there are factors calling for an adjustment or
       shifting of that line in order to achieve an ‘equitable result’.” 18

Three comments are appropriate. First, it follows from the position
that I have taken, in particular on the question of diﬀering values (see
paragraph 14) that I would have some diﬃculty with the last sentence in
that dictum, if by it the Court meant that in substance the equitable prin-
ciples/relevant circumstances method is similar to the equidistance/special
circumstances method. For there are clearly substantial diﬀerences
between the two methods. One such a diﬀerence may be found at the end
of the third sentence in the reference to adjustments of the equidistance
line in order to achieve an equitable result, a goal that has no application
to the median line/special circumstances method. If however, the Court was
merely referring to a procedural similarity between the two methods —
that is, in both cases one begins with a provisional median/equidistance
line, followed by consideration as to whether it should be adjusted —
I would have less diﬃculty with that analysis. Second, this was not a case
where the Court delimited all three maritime zones, as the Court was
not called upon to delimit the territorial sea in light of its ﬁnding that
that zone had already been delimited by previous agreements 19. Third,
at the time of this decision in Cameroon v. Nigeria, the Court had not
yet developed the three-stage approach in Black Sea. In the Black Sea
case 20 the Court outlined the three-stage methodology for the delimita-
tion of the EEZ and continental shelf. In the ﬁrst stage, a provisional
equidistance line is drawn; in the second stage, an examination is carried
out to determine whether there are any relevant circumstances requiring
an adjustment or shifting of that line; in the third stage, a check is carried
out to ensure that there is no disproportionality between the relevant
coasts and relevant areas to be delimited.

  17  Land and Maritime Boundary between Cameroon and Nigeria (Cameroon v.
Nigeria: Equatorial Guinea intervening), Judgment, I.C.J. Reports 2002, p. 303.
   18 Ibid., p. 441, para. 288.
   19 Ibid., p. 440, para. 285; p. 431, para. 268.
   20 Maritime Delimitation in the Black Sea (Romania v. Ukraine), Judgment,

I.C.J. Reports 2009, p. 61.

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257 maritime delimitation and land boundary (sep. op. robinson)

   17. The Black Sea approach, in particular, the third stage in which the
Court checks that there is no disproportionality, conﬁrms the diﬀerence
alluded to before, between the median line/special circumstances approach
under Article 15 and the equitable solution approach of Articles 74 and
83. The addition of the disproportionality test at the third stage in the
delimitation ensures that the focus of a delimitation under Articles 74 and
83 remains the achievement of “an equitable solution”. Under Article 15,
disproportionality, itself an element of equitableness, plays no role in the
delimitation of the territorial sea. Therefore, Cameroon v. Nigeria, is not
an authority for the proposition that the Court’s case law supports a uni-
form methodology for delimiting all three maritime zones.

  18. Another case that might appear to show the Court’s use of a uni-
form methodology for delimiting the three maritime zones is Peru v.
Chile 21. However, examination of that case shows that there is no basis
for that conclusion. It will be recalled that in Peru v. Chile the Court had
found that the Parties had agreed on their maritime boundary up to
80 nautical miles and therefore, began the delimitation at that endpoint 22.
The question of delimitation of the territorial sea, therefore, did not arise.
Since the Court did not delimit all three maritime zones, that case can
hardly provide support for the proposition that the Court favours a single
method of delimitation for all three zones.

   19. Therefore, Articles 15, 74 and 83 properly interpreted, as well as
the case law of the Court, do not support the proposition that there is a
“convergence in maritime delimitation methodology” 23 for the delimita-
tion of the territorial sea, EEZ and the continental shelf. A case such as
Croatia v. Slovenia 24, which posits that there is such a convergence, must
be treated cautiously 25. In light of the fact that in that case the delimita-
tion of all three zones did not arise, the following statement at para-
graph 1000 is diﬃcult to understand:
          “In relation to the delimitation both of the territorial sea and of
        the maritime zones beyond the territorial sea, international law thus
        calls for the application of an equidistance line, unless another line is
        required by special circumstances. That is reﬂected in the practice of
        the ICJ, which has applied the ‘equidistance/special circumstances’

   21 Maritime Dispute (Peru v. Chile), Judgment, I.C.J. Reports 2014, p. 3.
   22 Ibid., p. 65, para. 177; p. 66, para. 183.
   23 CR 2017/11 (Lowe), p. 12, para. 15.
   24 Arbitration under the Arbitration Agreement between the Government of the Republic

of Croatia and the Government of the Republic of Slovenia, signed on 4 November 2009
(Croatia v. Slovenia), PCA Case No. 2012-04, Final Award of 29 June 2017.
   25 For discussion of this case, see Massimo Lando, “The Croatia/Slovenia Arbitral

Award of 29 June 2017: Is there a Common Method for Delimiting all Maritime Zones
under International Law?”, Rivista Di Diritto Internazionale, Vol. 100 (4), p. 1184.

122

258 maritime delimitation and land boundary (sep. op. robinson)

       approach in the drawing of single maritime boundaries without dis-
       tinguishing between its application to the territorial sea and its appli-
       cation beyond the territorial sea.” 26

In support of its ﬁnding that the Court’s practice favours a single meth-
odology for delimitation of the territorial sea and the maritime zones
beyond it, the Tribunal cites Cameroon v. Nigeria and Peru v. Chile.
However, as the analysis in paragraphs 16 to 18 of this opinion shows,
this is not the case.

   20. In the instant case, the Court drew a single maritime boundary, but
was explicit in applying the median line/special circumstances approach
in respect of the territorial sea, and the Black Sea three-stage approach,
incorporating the equidistance line/relevant circumstances and dispropor-
tionality tests, for the EEZ and continental shelf.

   21. Moreover, in accordance with Article 32 of the Vienna Convention
on the Law of Treaties, recourse may be had to the travaux préparatoires
for the purpose of conﬁrming the meaning resulting from the general rule
of interpretation. In that regard, reference has already been made to the
Venezuelan proposal in 1980 that the concept of equity should apply to
delimitation of the territorial sea, the EEZ and the continental shelf. The
rejection of that proposal supports the conclusion that unless the parties
have agreed otherwise, for the purposes of delimitation, the territorial sea
is treated diﬀerently from the EEZ and continental shelf, that is, there is
no convergence in maritime delimitation methodology in respect of the
three zones intended by the drafters of the Convention.

   22. The Venezuelan proposal is also relevant for another reason. In
order to substantiate its proposition of a convergence in maritime delimi-
tation methodology, Nicaragua attempted to show that Article 15 of
UNCLOS was simply transposed from the 1958 Convention on the Ter-
ritorial Sea and Contiguous Zone, thereby suggesting that the topic of the
territorial sea was somewhat uncontroversial. However, during the ninth
session of the Third Conference, Venezuela indicated that it could not
accept the wording of Article 15 because, in its view, the concept of equity
should inﬂuence the delimitation of all maritime spaces; for that reason it
proposed that Article 15 should be brought into line with Articles 74
and 83, which at that time included references to equitable considerations.
The introduction of the Venezuelan proposal shows that, at that time,
some countries had diﬃculties with the régime for delimitation of the ter-
ritorial sea; in particular, they did not accept the absence of a reference to
equitable principles in Article 15.

  26   Supra note 24, p. 311, para. 1000.

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259 maritime delimitation and land boundary (sep. op. robinson)

  23. I turn now to address an argument that may be said to favour
Nicaragua’s approach.
  24. Over the years, State practice in maritime delimitation has shown a
marked preference for a single maritime boundary delimiting the various
maritime areas. The Court itself has on some occasions been requested to
draw a single maritime boundary for the EEZ and the continental shelf as
well as the territorial sea, the EEZ and the continental shelf.

   25. Nicaragua interprets this practice as supporting its theory of
convergence in maritime delimitation methodologies. In the oral proceed-
ings it made several submissions in support of this proposition; for exam-
ple, it submitted that “UNCLOS Articles 15, 74 and 83 apply to the
drawing of diﬀerent segments of one continuous line” 27. It also submitted
that when the Court is asked to draw a territorial sea boundary, it is “a
reasonable presumption that it will draw it so that the part in the territo-
rial sea joins up with the part beyond the territorial sea” 28.
   26. A single delimitation line does not necessarily mean a single delim-
itation method, as the instant case and several others have shown. The
point is that even when a single delimitation line is employed, the segment
of the line delimiting the territorial sea will have an entirely diﬀerent legal
signiﬁcance from the segment of the line reﬂecting delimiting the EEZ
and continental shelf. For those segments would have been arrived at on
entirely diﬀerent legal bases: the ﬁrst on the basis of a median line, that
because it relates to an area where the rights of the coastal State are ter-
ritorial, remains virtually unassailable, and the second on the basis of a
median line, which because it relates to an area in which the rights of the
coastal State are only functional, is more susceptible to adjustment in the
search for an equitable solution. The best explanation for the advent of
the single delimitation line as an emerging practice in delimitation agree-
ments between States is the element of simplicity and convenience that it
oﬀers. Thus, the question whether this practice in any way supports the
claims for a single delimitation methodology must be answered in the
negative.
   27. The Court has employed the single line approach, but has always
distinguished between delimitation methods for the territorial sea on the
one hand, and those for the EEZ and continental shelf on the other 29. It
follows from the position I have taken in paragraphs 16 to 18 that I do
not treat as true examples of a uniform approach, Cameroon v. Nigeria
and Peru v. Chile, since in those cases the Court did not have to delimit
all three maritime areas.

  27  CR 2017/11 (Lowe), p. 12, para. 16.
  28  Ibid., p. 13, para. 16.
   29 See for example, Maritime Delimitation and Territorial Questions between Qatar

and Bahrain (Qatar v. Bahrain), Merits, Judgment, I.C.J. Reports 2001, pp. 94-110,
paras. 178-223.

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260 maritime delimitation and land boundary (sep. op. robinson)

   28. In Nicaragua v. Honduras, despite the exceptional circumstances of
the case, the Court was careful to stress that the median line remains “the
general rule” 30. In Qatar v. Bahrain, where the Court was asked to deter-
mine the course of a single maritime boundary for the territorial sea, EEZ
and continental shelf, it stated that delimitation of the EEZ and the con-
tinental shelf “does not present comparable problems [to delimitation of
the territorial sea] since the rights of the coastal State in the area con-
cerned, [territorial sea] are not functional but territorial, and entail sover-
eignty over the sea-bed and the super adjacent waters and air column” 31.

   29. No development after 1982 has changed the marked distinction
made by the Convention and aﬃrmed by the Court between delimitation
of the territorial sea on the one hand, and that of the EEZ and continen-
tal shelf on the other. At the First United Nations Conference on the Law
of the Sea (UNCLOS I) in 1958, Sir Gerald Fitzmaurice, the United
Kingdom’s Representative said, in respect of the territorial sea: “for rea-
sons of equity . . . special circumstances may exist which could make it
diﬃcult to accept the true median line as the actual line of delimitation” 32.
However, as is patent, that comment was made long before the adoption
of the Convention in 1982, which eﬀected a bifurcation between the
delimitation of the territorial sea on the one hand, and delimitation of the
continental shelf and EEZ on the other. Today, as a result of the
UNCLOS, it will not avail a disgruntled State (party to the Convention)
to aver that the delimitation of its territorial sea has not produced an
equitable solution, if that term is used synonymously with “equitable
solution” in Article 74 and 83 of UNCLOS.
   30. Today there is certainly less leeway for departing from the median
line in the territorial sea on the basis of special circumstances than there
is for departing from the equidistance line in the EEZ and continental
shelf on the basis of relevant circumstances in the search for an equitable
solution. The special circumstances must indeed be very special to war-
rant adjustment to or departure from the median line in the territorial
sea; for example, in the Nicaragua v. Honduras case, due to geomorpho-
logical conditions at the mouth of the River Coco, it was not possible to
identify suitable base points for the drawing of the median line and the
Court therefore used the angle-bisector method 33.

   31. Prior to 1982, in view of the similarity in the provisions for delimi-
tation relating to the territorial sea and the continental shelf, it may have
been correct to speak of a unity of delimitation methods for both zones.

  30  Supra note 13, I.C.J. Reports 2007 (II), p. 745, para. 281.
  31  Supra note 29, I.C.J. Reports 2001, p. 94, para. 174.
   32 Satya N. Nandan and Shabtai Rosenne (eds.), United Nations Convention on the

Law of the Sea 1982: A Commentary, Vol. II, Martinus Nijhoﬀ Publishers, 1985, p. 135,
para. 15.2.
   33 Supra note 13, I.C.J. Reports 2007 (II), pp. 742-743, paras. 277-280.

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261 maritime delimitation and land boundary (sep. op. robinson)

However, today it is not correct to say that equity or equitable principles
apply to the territorial sea, if those terms are used synonymously with the
term “equitable solution” in Articles 74 and 83. Such a conclusion is con-
tradicted by the plain reading of the relevant articles, and the drafting
history of the Conference, in which — after eight years of negotiations
that expressly considered the use of the median line or equitable princi-
ples for the delimitation of the EEZ — 158 countries decided on a formu-
lation for the EEZ that focused on an equitable solution. The phrase
“equitable solution” has therefore become a term of art and its usage
should be conﬁned to the situations covered by Articles 74 and 83.

                                Conclusions

  I. Properly interpreted, Articles 15, 74 and 83 of the UNCLOS call for
     a dichotomous approach in the delimitation methodology for the ter-
     ritorial sea on the one hand, and the EEZ and continental shelf on
     the other.
 II. However, it is possible under the Convention for States to agree to
     utilize a uniform method.
III. It is the diﬀerence in the legal régime for the territorial sea on the one
     hand and the EEZ and continental shelf on the other, that explains
     why the Convention calls for a dichotomous approach in maritime
     delimitation methodology.
IV. Diﬀerent values are attached to the various elements relevant to the
     delimitation in the various zones. Thus, the provisional median line
     in the territorial sea has a diﬀerent value from the provisional equi-
     distance line in the EEZ and continental shelf and similarly, special
     circumstances in the territorial sea will have a diﬀerent value from
     relevant circumstances in the EEZ and continental shelf. If one were
     to apply the territorial sea-median line/special circumstances method
     to the EEZ and continental shelf, one would have to do so fully sen-
     sitive to the fact that the provisional equidistance line in the EEZ and
     continental shelf will be more susceptible to adjustment than the pro-
     visional median line in the territorial sea.

V. The Court has used the dichotomous approach consistently in its
    work, and generally, so have arbitral tribunals.
VI. The three-stage approach set out in the Black Sea case is a major
    development in the Court’s case law, but it has in no way aﬀected the
    dichotomous approach employed by the Court. In fact, it has served
    to conﬁrm that approach.

                                          (Signed) Patrick L. Robinson.

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