1. Causes of Action

3. RELEVANT DEFINITIONS AND ESSENTIAL ELEMENTS

The precise grounds for judicial review are different across jurisdictions, but the core principle is that a legal challenge may be brought against a decision made by a government decision-maker on the basis that the law has not been correctly applied. The focus of judicial review is whether the correct legal process for reaching a decision was followed and whether the decision maker used its powers correctly. Thus, there is limited scope for challenging the actual merits of a decision.

The elements set out here focus on judicial review in Australia and the UK, as two jurisdictions where the majority of climate litigation has been in the form of challenges to government decisions on planning and permitting.

In Australia, the grounds for judicial review in the Federal Court have been codified in the Administrative Decisions (Judicial Review) Act 1977, according to which a decision made by a person exercising a 'public function' can be reviewed on any one or more of the following grounds:[5]

5  Applications for review of decisions

(1) A person who is aggrieved by a decision to which this Act applies that is made after the commencement of this Act may apply to the Federal Court or the Federal Circuit and Family Court of Australia (Division 2) for an order of review in respect of the decision on any one or more of the following grounds:
(a) that a breach of the rules of natural justice occurred in connection with the making of the decision;
(b) that procedures that were required by law to be observed in connection with the making of the decision were not observed;
(c) that the person who purported to make the decision did not have jurisdiction to make the decision;
(d) that the decision was not authorized by the enactment in pursuance of which it was purported to be made;
(e) that the making of the decision was an improper exercise of the power conferred by the enactment in pursuance of which it was purported to be made;
(f) that the decision involved an error of law, whether or not the error appears on the record of the decision;
(g) that the decision was induced or affected by fraud;
(h) that there was no evidence or other material to justify the making of the decision;
(j) that the decision was otherwise contrary to law.

(2) The reference in paragraph (1)(e) to an improper exercise of a power shall be construed as including a reference to:
(a) taking an irrelevant consideration into account in the exercise of a power;
(b) failing to take a relevant consideration into account in the exercise of a power;
(c) an exercise of a power for a purpose other than a purpose for which the power is conferred;
(d) an exercise of a discretionary power in bad faith;
(e) an exercise of a personal discretionary power at the direction or behest of another person;
(f) an exercise of a discretionary power in accordance with a rule or policy without regard to the merits of the particular case;
(g) an exercise of a power that is so unreasonable that no reasonable person could have so exercised the power;
(h) an exercise of a power in such a way that the result of the exercise of the power is uncertain; and
(j) any other exercise of a power in a way that constitutes abuse of the power.

(3) The ground specified in paragraph (1)(h) shall not be taken to be made out unless:
(a) the person who made the decision was required by law to reach that decision only if a particular matter was established, and there was no evidence or other material (including facts of which he or she was entitled to take notice) from which he or she could reasonably be satisfied that the matter was established; or
(b) the person who made the decision based the decision on the existence of a particular fact, and that fact did not exist.

In the UK, a claimant can challenge a decision made by a public body on one or more of the following grounds for judicial review: 1) illegality, 2) irrationality, and 3) procedural impropriety. These were set out by Lord Diplock in Council of Civil Service Unions v Minister for the Civil Service (the 'GCHQ case') [1985] AC 374:

For a decision to be susceptible to judicial review the decision-maker must be empowered by public law (and not merely, as in arbitration, by agreement between private parties) to make decisions that, if validly made, will lead to administrative action or abstention from action by an authority endowed by law with executive powers
...
one can conveniently classify under three heads the grounds upon which administrative action is subject to control by judicial review. The first ground I would call "illegality," the second "irrationality" and the third "procedural impropriety."
...
By "illegality" as a ground for judicial review I mean that the decision-maker must understand correctly the law that regulates his decision-making power and must give effect to it. Whether he has or not is par excellence a justiciable question to be decided, in the event of dispute, by those persons, the judges, by whom the judicial power of the state is exercisable.

By "irrationality" I mean what can by now be succinctly referred to as "Wednesbury unreasonableness" (Associated Provincial Picture Houses Ltd. v. Wednesbury Corporation [1948] 1 KB 223). It applies to a decision which is so outrageous in its defiance of logic or of accepted moral standards that no sensible person who had applied his mind to the question to be decided could have arrived at it.
...
I have described the third head as "procedural impropriety" rather than failure to observe basic rules of natural justice or failure to act with procedural fairness towards the person who will be affected by the decision. This is because susceptibility to judicial review under this head covers also failure by an administrative tribunal to observe procedural rules that are expressly laid down in the legislative instrument by which its jurisdiction is conferred, even where such failure does not involve any denial of natural justice.

[5] These grounds are a restatement of the grounds under Australian common law and so also apply at the state level.