Quick initial thoughts on the friends of the Irish Environment case from a brief skim. It's a very significant case for several reasons, some of environmental policy, some of major constitutional law, and some of wonkish constitutional law.

The Court held that the National Mitigation Plan is Ultra Vires the s 4 of Climate Action and Low Carbon Development Act 2015, which required that the plan have a sufficient level of specificity in the measures set out so that a reasonable and interested person could...

make a judgement on whether they agree with the plan's approach to meeting the National Transitional Objectives by 2050. The Court found, on detailed reasoning, that the Plan "falls well short" of that level and so fails to meet the statutory requirements.

The Court said it was not impermissibly interfering with policy because, with s 4 of the 2015 Act, "policy became law" and the matter became justiciable. Policy matters in general do not fall within the bailiwick of the courts in our separation of powers. However...

additional of the policy into law or the impingement of rights might give the courts a role. On the rights questions:

The Court found that FIE does not have standing to raise rights-based arguments related to life and bodily integrity which it does not personally enjoy, and does not enjoy a standing exemption on the basis that raising these arguments would be impossible or excessively difficult.

But the court went on to express some view on the rights question, if not to decide them. It sets out a general preference for rights not found in the text of the Constitution being "derived rights rather than unenumerated rights", eg privacy and not being denied ability to work.

This stresses that "there must be some root of title in the text or structure of the Constitution from which the right in question can be derived. It may stem, for example, from a constitutional value such as dignity when taken with other express rights and obligations".

However, it cannot be "simply from judges looking into their hearts and identifying which rights they think must should be in the Constitution". They must be derived "from the Constitution as a whole". Such an approach would leave the separation of powers "truly blurred".

However, the right to a healthy environment asserted by FIE was either "impermissibly vague" and imprecise, or not extending beyond the rights to life and bodily integrity already recognised, to be a derived right.

The Court noted that in most states where there were environmental constitutional rights, these had been textually inserted by amendment. But there "may well be cases, which are environmental in nature, where constitutional rights and obligations may be engaged."

Indeed, if the plaintiff had standing to make rights arguments, they may have been engaged here. This seems to show a willingness of the court to engage with rights and/or constitutional duties in future environmental litigation. This passage is particularly significant:

"I would not rule out the possibility that the interplay of existing constitutional rights with the constitutional values to be found in the constitutional text and other provisions, such as those to be found in Art. 10 and also the right to property and the special position of..

the home, might give rise to specific obligations on the part of the State in particular circumstances. Exactly how any such rights or obligations should be characterised" must wait for an appropriate case.

TLDR: a really major constitutional, as well as environmental, judgment. One of the most important statements on rights in a generation, and offering signs of how personal rights and constitutional duties may feature in the environmental context in future.

Couple of additional points to add: the judgement is very well written despite being turned around very quickly it; it's a unanimous judgment of 7 judge court; and it has the feeling of the Court making a landmark statement to echo far beyond this case.