The Oxford Guide to Treaties Symposium: Treaty Reservations and ‘Objections-to-Reservations’

[David P. Stewart is a Visiting Professor of Law at Georgetown University Law Center]

Duncan Hollis deserves hearty congratulations on the publication of the Oxford Guide to Treaties.  There’s no doubt that it will quickly become the essential reference for lawyers and other treaty specialists in foreign ministries and international organizations everywhere, to say nothing of judges, professors and private practitioners.  Its 25 substantive chapters cover the full range of issues raised by contemporary treaty practice, both bilateral and multilateral, so it’s definitely not a volume you’ll try to read at one sitting.   But international lawyers will certainly want to keep it handy.   Many thanks to Duncan and his co-authors for giving us one of those “can’t-do-without” books.

For various reasons, I was drawn in particular to Ed Swaine’s chapter on treaty reservations and was delighted to find a thorough and thoughtful analysis which combines practice and theory and contrasts the rules of the Vienna Convention on the Law of Treaties with the International Law Commission’s 2011 Guide to Practice.   He traces the evolution of the reservations system as multilateral treaties proliferated over the past century and takes up the knottiest of issues – for example, how reservations differ from other unilateral statements (such as interpretive statements or “understandings”), whether some types of reservations are void ab initio or only when objected to by other States, and what legal effect such “objections” actually have — and who gets to decide.

As Swaine rightly notes, the “objections-to-reservations” rules in VCLT articles 20 and 21 leave much to be desired, at least with respect to clarity and certainty.  An objecting State can, at its option, decline to accept treaty relations with the reserving state; otherwise, “the provisions to which the reservation relates do not apply as between the two States to the extent of the reservation.”  (Art. 21(3)).

The ILC’s Guide reiterates the first part of this approach (noting, in para. 2.6.6, that a state or international organization “may oppose the entry into force of the treaty as between itself and the author of the reservation”) but then introduces a further complication by distinguishing between “valid” and “impermissible” reservations and by introducing the concept of “establishing” a reservation.  In summary, an “established” reservation is one which is authorized by the treaty or otherwise permissible, properly formulated and communicated, and accepted by the other party (para. 4).  By definition, then, established reservations are objection-proof (or, put otherwise, objections prevent establishment.) But an objection to a reservation which has not been “established,” even if that reservation is “valid,” has the legal effect of precluding the reservation “from having its intended effects” but does not preclude the entry into force of the treaty as between the reserving and objecting states, unless the objecting state expresses such an intention (para. 4.3, 4.3.1 and 4.3.5).  Whether this additional level of detail adds to the clarity of the rules seems questionable.

These issues get even more difficult when the objection is to only part of a reservation (a subject not explicitly addressed by the Convention or the ILC Guide).   But perhaps the most troubling recent development in recent “treaty reservation practice” has been the emergence of a so-called “severability” rule – according to which some reservations are considered invalid or impermissible and therefore “severable,” meaning that the reserving state is bound to the treaty in question without the benefit of its asserted reservation.  The origins of this approach, as Swaine notes, lie in the European Court of Human Rights (in particular its 1988 decision in the Belilios case); the UN Human Rights Committee adopted a similar approach in its General Comment 24 (1994) formulated in the context of the International Covenant on Civil and Political Rights.  Although the Covenant contains no prohibitions on reservations, the Committee adopted a very restrictive view on the subject, opining that no reservations could be taken to provisions that represent customary international law (and a fortiori those having the character of peremptory norms), or that make rights non-derogable, or that provide “supportive guarantees,” or that interfere with its own “monitoring role” or its competence to interpret the requirements of the Covenant.  The General Comment drew immediate and sharp protests from the United States, the United Kingdom and France for a variety of reasons, among them the suggestion that the Committee could itself declare a given reservation invalid and “severable” and consider the reserving State bound to the Covenant without benefit of the reservation in question.

A simple illustration demonstrates why the Committee’s approach was of such concern to the United States.   Article 20 of the Covenant provides that “any propaganda for war shall be prohibited by law” and that “any advocacy of national, racial or religious hatred that constitutes incitement to discrimination, hostility or violence shall be prohibited by law.”  For obvious First Amendment reasons, the United States could not comply with the full import of that article, and thus conditioned its adherence to the Covenant on a carefully crafted reservation stating that “article 20 does not authorize or require legislation or other action by the United States that would restrict the right of free speech and association protected by the Constitution and laws of the United States.”  But the Committee took direct aim at this reservation, declaring that a state may not reserve the right to permit the advocacy of national, racial or religious hatred, because that prohibition was a matter of customary international law (if not a peremptory norm).

It is possible that the Committee failed to understand the real import of its statement, since it would leave denunciation of the Covenant as the only real option.  Had General Comment been issued before the United States undertook to adhere to the Covenant, ratification would have been far less likely.  Had the severability doctrine been understood to apply, it is hard to see how any responsible legal or political adviser could have recommended U.S. ratification in the first place.  The example simply illustrates that restrictive reservation rules may well work against broad adherence to some types of multilateral treaties, as Swaine’s chapter notes.

The ILC Guide takes a more nuanced approach than General Comment 24.  It states clearly that the fact a treaty provision reflects a rule of customary international law “does not in itself constitute an obstacle to the formulation of a reservation” but that no reservation can exclude or modify the effect of a treaty contrary to a peremptory norm.  (paras. 3.1.5.3, 4.4.2).  Nor can reservations be taken to non-derogable provisions unless “compatible with the essential rights and obligations arising out of that treaty.” (para. 3.1.5.4).  A somewhat similar tack is taken to reservations concerning dispute settlement provisions or monitoring (para. 3.1.5.7).  On the question of severability, the Guide states that unless it has expressed a contrary intention, a state is bound to the treaty without the benefit of an invalid reservation.

In an ideal world, “clean” ratifications are much to be desired.  But as multilateral treaties become more detailed and seek to address more issues on which various domestic laws and practices differ widely, it grows commensurately more difficult to achieve agreement on texts which all states can accept and implement.   Perfection in drafting is a virtue attributable to few if any treaties, especially those produced in multilateral fora.  Within limits, therefore, reservations continue to serve a useful function, permitting states to adhere to imperfect treaty texts by providing a means of accommodating differences.  In practice, the severability rule may turn out to be a significant disincentive to broad treaty adherence – particularly when decisions about the validity of reservations no longer rest on state consent.