Is the Paris Agreement “legally binding”?
 
Many are saying that the Paris Agreement is not legally binding.  That is not true, says Dean Bialek of Independent Diplomat, who explains here:

First, the Paris Agreement is in the form of an internationally legally binding instrument that must be approved under Parties' respective domestic ratification processes, including approval by executive and in some cases parliamentary processes.  Legally, there is no higher or more serious level of commitment at the international level.

Second, and more specifically on the provisions of the Agreement itself, like all international legal instruments, the Paris Agreement has many provisions that impose legally binding obligations (those that use the verb “shall”), and also others that are descriptive, hortatory or aspirational.  It is clear that the Paris Agreement imposes numerous legally binding obligations on all countries that sign up to it – large and small, developed and developing.  For example, all countries have accepted a legally binding obligation to communicate a new emissions reduction or limitation target (“nationally determined contribution”) every five years, to regularly submit information on how they are tracking towards meeting those targets, and also to subject that information to technical expert review to assess its comprehensiveness and accuracy, and identify areas for improvement.

Third, on the bindingness of emission reduction efforts, although the Agreement does not legally require countries to achieve the numerical emission reduction targets they have set, it does legally bind them to an obligation to “pursue domestic mitigation measures” with the aim of achieving the objectives (i.e. targets) they have set for themselves.  So submitting an emissions target and doing nothing to put it into practice would be a legal breach of the new Agreement.  To give this obligation some teeth, the Paris Agreement will establish a committee to promote compliance with country’s obligations.  The Compliance Committee’s exact mandate and powers have been deliberately left broad for further definition in coming years, and so the more ambitious countries will continue to push hard for these powers to be as strong as possible.