Subsections (2) and (3) apply in relation to a decision by the Upper Tribunal—
to grant or refuse permission to appeal in response to an application under section 45(2) (permission to appeal: claims certified as clearly unfounded),
to grant or refuse an application for a declaration under section 46(4) (out of time claims), or
to make or not to make a determination under section 48(5)(b) (new matters).
The decision is final, and not liable to be questioned or set aside in any other court.
In particular—
the Upper Tribunal is not to be regarded as having exceeded its powers by reason of any error made in reaching the decision;
the supervisory jurisdiction does not extend to, and no application or petition for judicial review may be made or brought in relation to, the decision.
Subsections (2) and (3) do not apply so far as the decision involves or gives rise to any question as to whether—
the Upper Tribunal has or had a valid application before it under section 45(2) or 46(4),
the Upper Tribunal is or was properly constituted for the purpose of dealing with the application or, in the case of a decision mentioned in subsection (1)(c), for the purpose of making the decision, or
the Upper Tribunal is acting or has acted—
in bad faith, or
in such a procedurally defective way as amounts to a fundamental breach of the principles of natural justice.
In this section—
“decision” includes any purported decision;
“the supervisory jurisdiction” means the supervisory jurisdiction of— the High Court, in England and Wales or Northern Ireland, or the Court of Session, in Scotland.