OREANDA-NEWS. The new global climate deal to be agreed in Paris next month will not set legally binding emissions reduction obligations, but will oblige countries to submit a voluntary, nationally appropriate pledge.

Countries will have to report on progress and update their intended nationally determined contributions (INDC) in line with an agreed cycle, but they will not be bound to meet their pledge in international law.

This is the situation most likely to emerge from a range of possible legal formats for the deal, all with different degrees of enforceability, given the US administration's reluctance to ratify a legally binding climate treaty.

US foreign secretary John Kerry stirred controversy earlier this month when he said that the new deal will be no be legally binding and will not contain legally binding greenhouse gas (GHG) emissions reduction targets. But widespread criticism of his comments was somewhat surprising — and perhaps slightly misplaced — for two reasons.

Firstly, those following closely UN climate negotiations have long accepted that a Republican-controlled US would block an internationally binding climate treaty. To avoid the Paris deal suffering the same fate as the Kyoto protocol, which the US signed but never ratified, the legal format of the Paris deal must not require state endorsement. Kerry's comments may simply reflect the political reality of the power balance in the US, rather his personal convictions.

And who accused Kerry of undermining efforts to forge a legally binding deal overlook the legal complexities of the new agreement, which will fall be somewhere between binding and non-binding, rather than being one or the other.

The Paris deal will be a package of political and legal outcomes, containing a range of instruments with varying degrees of legal force. It will consist of a core agreement, countries INDCs, related decisions of the UN Conference of the Parties (Cop), and one or more political declarations. Binding and more durable elements will generally be placed in the core agreement, while more detailed elements that evolve over time will be outlined in Cop decisions. Alongside these, political declarations will capture broad vision and aspirational goals.

"It is necessary to assess the instrument as a whole in determining its legal nature on the spectrum between hard and soft law, binding and non-binding,"according to France's national centre for scientific research (CNRS).

With all options still on the table, it is worth considering the different legal forms that the Paris deal could take, the benefits and disadvantage of each — and the likelihood of it winning US support.

But it important to note that the agreement's strength or legal force will be determined not only by its legal form, but also by the "anchoring" of parties' commitments or INDCs in the core agreement; mechanisms for transparency, accountability and facilitation; and mechanisms for compliance.

And the precise language used and the prescriptiveness of its content will be decisive. Even a legally binding protocol can contain general provisions that are softly worded or formulated in ambiguous terms, so that they do not create legal rights and obligations.

The mandate agreed at the 2011 UN Framework Convention on Climate Change (UNFCCC) summit in Durban, South Africa, called for "a protocol, another legal instrument or an agreed outcome with legal force" under the UNFCCC applicable to all parties.

The Durban mandate was deliberately vague on the post-Kyoto deal's legal character to secure the broadest possible support among all UNFCCC parties. As a result, it has engendered the emerging bottom-up, voluntary, nationally appropriate, pledge-based policy architecture that is very different from the legally binding, economy-wide, quantified emissions-reduction obligations enshrined in the Kyoto protocol.

Legally the Durban mandate includes two main options: a "protocol" or "another legal instrument or an agreed outcome with legal force". A protocol would provide the greatest legal certainty — it would be a new, international treaty, legally binding under international law. Countries would enter the treaty as states, meaning their commitments will be enforceable and will survive changes in administration.

But a legally binding protocol would probably be blocked by a Republican-controlled US Congress. And other countries may be concerned about the potential costs of stringent, enforceable commitments too. Consequently, a protocol risks securing less participation and being less ambitious than a non-binding instrument such as a Cop decision.

The option of "another legal instrument" does not mean much, in as far as the terms "instrument" and "legal" are vague and generic, the CNRS said. And it is difficult to distinguish between a "legal instrument" and an "agreed outcome with legal force", because a legal instrument is not always legally binding, it said.

Ultimately, there two options can reasonably be considered: either a revision of the 1992 UNFCCC and/or its annexes; or a Cop decision or a set of Cop decisions, the CNRS said.

But a legally binding UNFCCC amendment is highly unlikely to receive US backing because it would require ratification — by at least three-quarters of parties to enter into force.

A Cop decision requires consensus to be adopted and can be applied immediately once adopted. But a Cop decision's legal standing is ambiguous in international law, because although it can have political force, it is not automatically legally binding. So what it adds in terms of flexibility and expedience, it loses in terms of legal security, the CNRS said.

Most parties have stated their preference for the adoption of a legally binding instrument in the form of a protocol to the UNFCCC, which would be complemented by a series of Cop decisions, the CNRS said. "This seems the best option because it gives the opportunity to optimise between the pros and cons of each option," it said.

This core treaty would be complemented by a series of Cop decisions that would allow flexible and swift implementation, despite the lower level of legal security that they provide. "With this multi-layer structure of the Paris agreement, the core provisions can be robust and durable, while the content of the treaty and its ambition can be progressively upgraded over time," the CNRS said.