399
requirement suitable not only for incidental issues of territorial sovereignty, but also
for other issues totally alien to the law of the sea against which geographical considerations might not have any sense. Otherwise, it could be said that this requirement applies only to territorial sovereignty issues, whereas other external issues
would be subject of incidental determinations depending on the quite delicate balance between the “incidental connection” and the “necessity” requirements.
Whatever view one takes, the requirement of the “minor” character of the external issue confirms that the Chagos test is discretionary-based. Even more than the
“inherently subject”
76
process of characterization of the dispute, that of determining
whether an issue is minor enough to be incidentally determined and, ultimately, the
extent of the incidental jurisdiction, inevitably refers to subjective considerations
depending on “the judge or arbitrator’s connection and sensitivities towards a
dispute”.
77
It remains to be seen whether and how UNCLOS Tribunals will develop a consistent approach on the issue and apply in practice the Chagos test. So far, this test
has only been incidentally formulated and simply provides matter for speculation.
5 Legal Effects of Incidental Determinations
A final important issue which neither the Chagos Tribunal nor other UNCLOS
Tribunals have yet addressed concerns the possible legal effects for the parties of
decisions on incidental issues. While it may be stated that, despite the difficulties in
determining and applying objectively its confines, courts and tribunals possess an
incidental jurisdiction over questions of merits which may be broader than the scope
of their principal jurisdiction, the question whether the res judicata or similar effects
are to be attached to the incidental determinations is still a matter of debate.
It should be first clarified that this question does not seem to concern those findings on external issues which are not “necessary” but simply relevant or desirable
for the principal determination. As already noted these findings reflect the relative
freedom of courts and tribunals to develop the reasons upon which the principal
determination is based. Strictly speaking, these findings are not “determinations” as
they do not consist in establishing rights and obligations for the parties or whether
a violation has been committed through the application of law to the relevant facts.
They are only “considerations”, consisting in the taking into account of external
the Guyana v. Suriname case by Christopher Greenwood, acting as counsel on behalf of Guyana:
“there is also the question of what is exactly meant by an incidental jurisdiction or perhaps what
are the limits of an incidental jurisdiction. You have to determine a maritime boundary, one little
island with just a couple of palm trees, how about two islands? What about a whole archipelago.
Does it matter whether they are inhabited or uninhabited?” (Hearing Day 5, 13 December 2006,
p. 798: 22–25 and p. 799: 1–2).
76 Talmon (2016), p. 934.
77 Crosato Neumann (2015).
Between Consent and Effectiveness: Incidental Determinations and the Expansion…
requirement suitable not only for incidental issues of territorial sovereignty, but also
for other issues totally alien to the law of the sea against which geographical considerations might not have any sense. Otherwise, it could be said that this requirement applies only to territorial sovereignty issues, whereas other external issues
would be subject of incidental determinations depending on the quite delicate balance between the “incidental connection” and the “necessity” requirements.
Whatever view one takes, the requirement of the “minor” character of the external issue confirms that the Chagos test is discretionary-based. Even more than the
“inherently subject”
76
process of characterization of the dispute, that of determining
whether an issue is minor enough to be incidentally determined and, ultimately, the
extent of the incidental jurisdiction, inevitably refers to subjective considerations
depending on “the judge or arbitrator’s connection and sensitivities towards a
dispute”.
77
It remains to be seen whether and how UNCLOS Tribunals will develop a consistent approach on the issue and apply in practice the Chagos test. So far, this test
has only been incidentally formulated and simply provides matter for speculation.
5 Legal Effects of Incidental Determinations
A final important issue which neither the Chagos Tribunal nor other UNCLOS
Tribunals have yet addressed concerns the possible legal effects for the parties of
decisions on incidental issues. While it may be stated that, despite the difficulties in
determining and applying objectively its confines, courts and tribunals possess an
incidental jurisdiction over questions of merits which may be broader than the scope
of their principal jurisdiction, the question whether the res judicata or similar effects
are to be attached to the incidental determinations is still a matter of debate.
It should be first clarified that this question does not seem to concern those findings on external issues which are not “necessary” but simply relevant or desirable
for the principal determination. As already noted these findings reflect the relative
freedom of courts and tribunals to develop the reasons upon which the principal
determination is based. Strictly speaking, these findings are not “determinations” as
they do not consist in establishing rights and obligations for the parties or whether
a violation has been committed through the application of law to the relevant facts.
They are only “considerations”, consisting in the taking into account of external
the Guyana v. Suriname case by Christopher Greenwood, acting as counsel on behalf of Guyana:
“there is also the question of what is exactly meant by an incidental jurisdiction or perhaps what
are the limits of an incidental jurisdiction. You have to determine a maritime boundary, one little
island with just a couple of palm trees, how about two islands? What about a whole archipelago.
Does it matter whether they are inhabited or uninhabited?” (Hearing Day 5, 13 December 2006,
p. 798: 22–25 and p. 799: 1–2).
76 Talmon (2016), p. 934.
77 Crosato Neumann (2015).
Between Consent and Effectiveness: Incidental Determinations and the Expansion…