1. Are there examples in international law where there is more than one protocol to the same treaty?
2. Does the subject matter of the two (or more) protocols overlap, complement or contradict each other?
3. If they do overlap, complement or contradict each other, how is this issue resolved between the protocols (i.e. how do you know which set of rules is intended to take precedence?
4. Is there an issue where a party ratifies one of the protocols but not the other?
5. Do any of these examples have conditions written into one protocol in respect of the other (e.g. parties can only reap the benefit of the protocol they choose to ratify if they ratify the other as well?)
6. If there are no relevant examples, what kinds of issues need to taken into account in the context of the UNFCCC if there is a 2 protocol outcome and how could these be resolved?
International law in relation to multiple protocols under a single treaty
There are numerous examples in international law of more than one protocol applying to a single treaty. Examples can found in a variety of different areas, including human rights, trade, and environment, such as:
(a) United Nations Convention Against Transnational Organised Crime 2000 (UN CATOC)- 3 protocols;
(b) United Nations Convention for the Protection of Cultural Property in the Event of Armed Conflict – 2 protocols
(c) United Nations Convention on Third Party Liability in the Field of Nuclear Energy 1960 (Paris Convention) – 3 protocols (including Joint Protocol Relating to the Application of the Vienna Convention on Civil Liability for Nuclear Damage 1963 (Nuclear Damage Vienna Convention) and the Paris Convention (Joint Protocol))
(d) General Agreement in Trade in Services (GATS) – 5 protocols
(e) Treaty of Amity and Cooperation in South East Asia (TACSEA) – 2 protocols
The purpose of each of the protocols to the treaties referred to above varies and therefore, so does the interaction between the protocols to each treaty.
In some cases, the purpose of the protocol is to amend a previous protocol or even the main treaty. For example, the second and fifth protocols to the GATS update the financial services sections of the Schedule of Specific Commitments and the List of Article II Exemptions of Members by way of replacement of the whole of that section with the new section set out in the relevant protocol. As such, there is no contradiction or overlap (however, as to how States who are not parties to both protocols interact with States who are parties to both protocols see paragraph 1.3 below which sets out Article 30(4) of the Vienna Convention).
Whereas in other cases, the purpose of a protocol may be to deal with a discrete topic within a treaty that covers a wide-ranging subject. In this way, the protocols are supplementary rather than overlapping, and allow for attention to be paid to particular issues at particular times. For example, the 3 protocols under the UN CATOC are each concerned with discrete subject matters under the general subject of the promotion of international cooperation to prevent and combat transnational organised crime. The first protocol focuses specifically on preventing and combating the smuggling of migrants. The second protocol focuses on preventing and combating trafficking persons, paying particular attention to women and children. The third protocol focuses on preventing and combating the illicit manufacturing and trafficking in firearms. The UN CATOC provides the framework for dealing with issues that are comment to all three protocols such as information exchange, border measures, and security and control of documents.
Other protocols have the purpose of clarifying the interaction between a treaty and international law. For example, the Second Protocol to the United Nations Convention for the Protection of Cultural Property in the Event of Armed Conflict establishes additional procedures to the Convention, in particular, how principles in the Convention interact with international humanitarian law, as in Article 6(b) of the Second Protocol which provides that:
…with the goal of ensuring respect for cultural property in accordance with Article 4 of the Convention, a waiver on the basis of imperative military necessity pursuant to Article 4 paragraph 2 of the Convention may only be invoked to use cultural property for purposes which are likely to expose it to destruction or damage when and for as long as no choice is possible between such use of the cultural property and another feasible method for obtaining similar military advantage.
Finally, in at least one case, a protocol has the purpose of eliminating conflicts between treaties which deal with a similar topic. Under the Joint Protocol , the contracting parties desire to establish a link between the Nuclear Damage Vienna Convention and the Paris Convention by mutually extending the benefit of the special regime of civil liability for nuclear damage set forth under each Convention and to eliminate conflicts arising from the simultaneous applications of both Conventions to a nuclear incident. The Joint Protocol provides guidance in relation to the application of the Nuclear Damage Vienna Convention and the Paris Convention. For example, Article IV provides that “Articles I to XV of the [Nuclear Damage] Vienna Convention shall be applied, with respect to the Contracting Parties to this Protocol which are Parties to the Paris Convention, in the same manner as between Parties to the [Nuclear Damage] Vienna Convention“.
In addition to any specific provisions which may be included in successive treaties on the same subject, the Vienna Convention on the Law of Treaties (Vienna Convention) provides rules which deal with potential conflicts:
Article 30 – Application of successive treaties relating to the same subject matter
1. Subject to Article 103 of the Charter of the United Nations, the rights and obligations of States parties to successive treaties relating to the same subject matter shall be determined in accordance with the following paragraphs.
2. When a treaty specifies that it is subject to, or that it is not to be considered as incompatible with, an earlier or later treaty, the provisions of that other treaty prevail.
3. When all parties to the earlier treaty are parties also to the later treaty but the earlier treaty is not terminated or suspended in operation under article 59 [of the Vienna Convention], the earlier treaty applies only to the extent that its provisions are compatible with those of the later treaty.
4. When the parties to the later treaty do not include all the parties to the earlier one:
(a) as between States party to both treaties the same rule applies as in paragraph 3;
(b) as between a State party to both treaties and a State party to only one of the treaties, the treaty to which both States are parties governs their mutual rights and obligations.
5. Paragraph 4 is without prejudice to Article 41 [of the Vienna Convention], or to any question of the termination or suspension of the operation of a treaty under article 60 [of the Vienna Convention] or to any question of responsibility which may arise for a State from the conclusion or application of a treaty the provisions of which are incompatible with its obligations towards another State under another Treaty.
Article 30 clearly does not cover all eventualities in relation to possible conflicts and as such, problems that arise may need to be dealt by the principles of international law if the treaty or Article 30 do not expressly deal with a conflict situation.
As to the query in relation to the benefits of one treaty being tied to a party entering into another treaty, we are not aware of such a condition being imposed. It seems unlikely to us that such a condition would be included in a treaty because it would be of no effect on States who did not adopt the second treaty (assuming that it is the second treaty which imposes the relevant obligation). However, we note that as under the Kyoto Protocol, a subsequent treaty can include provisions that it is only open to members of the original treaty 
Specific issues relating to second and subsequent protocols to the UNFCCC
As can be seen from the examples provided in paragraph 1.1 above, it is not unusual for a treaty to be supplemented or amended by subsequent protocols. The existence of multiple protocols need not mean that the administration of a treaty is difficult to implement. Of course, care should be taken to draft any additional protocols in a manner that does not create conflicts between the existing treaty (and protocols) and the later protocol. Another key to the workability of a treaty which has multiple protocols or other amending instruments, is for as many of the original States to a treaty also becoming parties to the subsequent treaties.
Many issues need to be considered if an additional protocol is to be added to the UNFCCC and many such issues are being considered in various forums including in the UNFCCC negotiations themselves. Just as there are a significant number of issues associated with creating a new protocol under the UNFCCC, so are there many possible solutions. The following are an example of some issues:
To the extent that a second protocol adds to the commitments or subject matter of the Kyoto Protocol (e.g. guidance on specific sectors such as REDD, aviation or shipping) then the following are some issues for consideration:
- parties to the second protocol not including all parties to the UNFCCC or the Kyoto Protocol. If the second protocol, for example, adds additional commitments and commitment periods which follow on from the commitments in the Kyoto Protocol, how many parties must adopt the new protocol in order for the commitments to be workable?;
- are there subject matters which could be appropriately dealt with under a new protocol without making wholesale amendments to either the UNFCCC or the Kyoto Protocol i.e. supplementary topics? As noted in paragraph 1.1 above, a treaty which covers a broad-ranging subject matter may benefit from protocols which deal with specific issues in specific ways;
- can (and should) new commitments be administered under existing administrative structures e.g. can (and should) “fast-track funding” contemplated by the Copenhagen Accord be administered under the Kyoto Protocol Adaptation Fund Board process or under the UNFCCC processes or a new process specific to the new protocol? The solution to this would involve consideration both the legality and the political palatability of the proposal.
- how will conflicts between the new protocol and the Kyoto Protocol or UNFCCC be dealt with – under the Vienna Convention and international law principles or a specific provision in the protocol?
To the extent that a second protocol substitutes or otherwise overrides the provisions of the Kyoto Protocol, then the following are some issues for consideration:
- parties to the second protocol being different from the parties to the Kyoto Protocol (see comments at paragraph 2.2(a)(i) above). In the case of an “amendment” protocol, this could create a situation in which an amendment applies to some States but not others (because the other State is a party to the UNFCCC/Kyoto Protocol but not a party to the new protocol). But this may not necessarily result in a negative outcome. For example, the United States is not a party to the Kyoto Protocol but is a party to the UNFCCC, so could become a member of a subsequent UNFCCC protocol which includes new commitment targets and timeframes. This has been the subject of much public debate; and
- practical implications associated with the replacement of particular text. For example, replacing the sections of the Kyoto Protocol that provide for the development of rules and procedures which underpin the current flexible mechanisms (i.e. CDM, JI and ETS) would mean that new rules and procedures would need to be developed for those mechanisms or any new mechanism created under the new protocol. The time and cost associated with creating new administrative structures could mean significant delays in implementation; and
In terms of solutions to the issues raised above (and those that may exist but are not identified in this document), it is important to keep in mind that treaties are an agreement between States and can include innovative solutions (subject always to international law principles and the agreement of the States). Whilst there may be legal solutions to each of the issues, there must also be political agreement.
 Vienna Convention on the Law of Treaties, opened for signature 23 May 1969, 1155 UNTS 331 (entered into force 27 January 1980)
 Article 103 of the Charter of the United Nations provides that any conflict between the obligations of Members of the United Nations under the Charter and their obligations under any other international agreement, their obligations under the Charter prevail.
 The term “treaty” is defined in the Vienna Convention to mean “any international agreement concluded between States in written form and governed by international law, whether embodied in a single instrument or in two or more related instruments and whatever its particular designation“. Various nomenclatures are used by states when naming a treaty including convention, charter, pact, protocol, declaration and agreement.
 Article 41 provides for the circumstances in which two or more parties to a multilateral treaty may amend that treaty as between themselves (i.e. not all parties to the treaty are agreeing to the amendment)
 Article 17 of the UNFCCC provides that only Parties to the UNFCCC can be Parties to any protocol adopted under the UNFCCC; Article 24.1 of the Kyoto Protocol provides that only Parties to the UNFCCC can become Parties to the Kyoto Protocol.
 See note 10 re Parties to protocols under the UNFCCC must be Parties to the UNFCCC.