395
was actually exercised over non-UNCLOS issues being simply incidentally
connected to the UNCLOS dispute. For example, in Guyana v. Suriname, the Annex
VII tribunal expressly referred to the incidental character of the non-UNCLOS dispute relating to use of force by stating that “[t]he CGX incident of 3 June 2000 […]
may be considered incidental to the real dispute between the Parties”. In the same
vein, the idea that an incidental connection between the non-UNCLOS issue and the
UNCLOS dispute can afford a basis for the extension of Part XV jurisdiction over
the non-UNCLOS issue has been sustained by several States before UNCLOS
Tribunals.
58
However, it seems that a mere incidental connection with the real dispute cannot
alone let the non-UNCLOS issue fall within the jurisdiction of UNCLOS Tribunals.
Within a multifaceted dispute a potentially indefinite number of external issues can
be considered as incidental or ancillary to the “real dispute” properly falling within
Part XV jurisdiction. Moreover, the same incidental issue might, in turn, involve
other incidental issues still even more “external” to the real dispute. The two dissenting judges in Chagos indirectly envisaged this latter scenario when referred to
the possibility of the Tribunal considering the question of the alleged violation by
the UK of the principle of self-determination in the context of the separation of the
Chagos Archipelago from Mauritius.
59
It seems that, to the minority, this question
was ancillary to the (in their view) incidental issue of sovereignty over the Chagos
Archipelago and could be addressed by the Tribunal by applying Art. 293(1) on
applicable law.
60
Now, apart that this approach seems to further add to the controversial use of the applicable law clause by UNCLOS Tribunals,
61
it is self-evident
that the notion of incidental connection is extremely vague and risks to expand
excessively the jurisdiction of tribunals acting under Part XV.
That is the reason why the Tribunal in Chagos was right in requiring further
conditions. The incidental determination over the non-UNCLOS issue must be necessary to resolve the UNCLOS issue. This necessity requirement is in line with the
idea that the power to make incidental determinations is inherent to the jurisdiction
of courts and tribunals and stems from the concept of “extension of jurisdiction by
necessary implication”.
62
As seen, it finds some support in case law, as well as
among commentators. As former ITLOS Judge Eiriksson observed, “questions of
customary international law and other questions outside the four corners of the
Convention and other agreements would be addressed, were it necessary to reach a
58 See e.g. the Netherlands’ claim in the Arctic Sunrise case that “the violations of the relevant rules
of the law of the sea are reasonably related to violations of human rights under customary international law and the ICCPR”. Memorial of the Kingdom of the Netherlands, 31 August 2014, para.
131 (emphasis added). See also the Mauritius’ argument in the Chagos Marine Protected Area
Arbitration (reproduced at para. 177 of the Award).
59 Chagos Marine Protected Area Arbitration, Dissenting and Concurring Opinion of Judges
Kateka and Wolfrum, para. 67 ff.
60 Ibidem, para. 73.
61 See Nguyen (2016), p. 134.
62 Shihata (1965), p. 195 (emphasis added).
Between Consent and Effectiveness: Incidental Determinations and the Expansion…
was actually exercised over non-UNCLOS issues being simply incidentally
connected to the UNCLOS dispute. For example, in Guyana v. Suriname, the Annex
VII tribunal expressly referred to the incidental character of the non-UNCLOS dispute relating to use of force by stating that “[t]he CGX incident of 3 June 2000 […]
may be considered incidental to the real dispute between the Parties”. In the same
vein, the idea that an incidental connection between the non-UNCLOS issue and the
UNCLOS dispute can afford a basis for the extension of Part XV jurisdiction over
the non-UNCLOS issue has been sustained by several States before UNCLOS
Tribunals.
58
However, it seems that a mere incidental connection with the real dispute cannot
alone let the non-UNCLOS issue fall within the jurisdiction of UNCLOS Tribunals.
Within a multifaceted dispute a potentially indefinite number of external issues can
be considered as incidental or ancillary to the “real dispute” properly falling within
Part XV jurisdiction. Moreover, the same incidental issue might, in turn, involve
other incidental issues still even more “external” to the real dispute. The two dissenting judges in Chagos indirectly envisaged this latter scenario when referred to
the possibility of the Tribunal considering the question of the alleged violation by
the UK of the principle of self-determination in the context of the separation of the
Chagos Archipelago from Mauritius.
59
It seems that, to the minority, this question
was ancillary to the (in their view) incidental issue of sovereignty over the Chagos
Archipelago and could be addressed by the Tribunal by applying Art. 293(1) on
applicable law.
60
Now, apart that this approach seems to further add to the controversial use of the applicable law clause by UNCLOS Tribunals,
61
it is self-evident
that the notion of incidental connection is extremely vague and risks to expand
excessively the jurisdiction of tribunals acting under Part XV.
That is the reason why the Tribunal in Chagos was right in requiring further
conditions. The incidental determination over the non-UNCLOS issue must be necessary to resolve the UNCLOS issue. This necessity requirement is in line with the
idea that the power to make incidental determinations is inherent to the jurisdiction
of courts and tribunals and stems from the concept of “extension of jurisdiction by
necessary implication”.
62
As seen, it finds some support in case law, as well as
among commentators. As former ITLOS Judge Eiriksson observed, “questions of
customary international law and other questions outside the four corners of the
Convention and other agreements would be addressed, were it necessary to reach a
58 See e.g. the Netherlands’ claim in the Arctic Sunrise case that “the violations of the relevant rules
of the law of the sea are reasonably related to violations of human rights under customary international law and the ICCPR”. Memorial of the Kingdom of the Netherlands, 31 August 2014, para.
131 (emphasis added). See also the Mauritius’ argument in the Chagos Marine Protected Area
Arbitration (reproduced at para. 177 of the Award).
59 Chagos Marine Protected Area Arbitration, Dissenting and Concurring Opinion of Judges
Kateka and Wolfrum, para. 67 ff.
60 Ibidem, para. 73.
61 See Nguyen (2016), p. 134.
62 Shihata (1965), p. 195 (emphasis added).
Between Consent and Effectiveness: Incidental Determinations and the Expansion…