Investigatory Powers Tribunal (IPT) was created by Part IV of the Regulation of Investigatory Powers Act 2000 (RIPA). It lies outside the general tribunal structure and is linked to the Home Office though it has an eminent membership including three High Court Judges. The Tribunal's website contains much useful information.
Tribunal has handed down judgment in relation to the legality of the regime governing
the soliciting, receiving, storing and transmitting by UK authorities of
private communications in a case brought against the intelligence
agencies in respect of alleged interception activity involving UK and US
access to communications. The Complainants are Liberty, Privacy
International, Amnesty International and seven overseas human rights
(The National Council of Civil Liberties) & Ors v The Secretary of
State for Foreign And Commonwealth Affairs and Others  UKIPTrib
13_77-H (06 February 2015)
FOR THE REASONS SET OUT IN THE TRIBUNAL'S JUDGMENT
OF 5 DECEMBER 2014 ("THE FIRST JUDGMENT") AND THEIR JUDGMENT OF THIS
DATE ("THE SECOND JUDGMENT")
IT IS DECLARED
(i) THAT prior to the disclosures made and referred to in the
First Judgment and the Second Judgment, the regime governing the
soliciting, receiving, storing and transmitting by UK authorities of
private communications of individuals located in the UK, which have been
obtained by US authorities pursuant to Prism and/or (on the Claimants'
case) Upstream, contravened Articles 8 or 10 ECHR, but
(ii) THAT it now complies with the said Articles.
Unhappiness remains! Privacy International - GCHQ-NSA intelligence sharing unlawful, says UK surveillance tribunal - notes that:
"While we welcome today’s decision, Privacy International and Bytes for All disagree with the tribunal’s earlier conclusion
that the forced disclosure of a limited subset of rules governing
intelligence-sharing and mass surveillance is sufficient to make GCHQ’s
activities lawful as of December 2014. Both organisations will shortly
lodge an application with the European Court of Human Rights challenging
the tribunal’s December 2014 decision."
RIPA 2000 s67(8) is worth noting - "Except to such extent as the Secretary of State may by order otherwise provide, determinations, awards, orders and other decisions of the Tribunal (including decisions as to whether they have jurisdiction) shall not be subject to appeal or be liable to be questioned in any court."
Thus it appears that the decision on a question of law by this Tribunal is not subject to an appeal to either the Court of Appeal or to the UK Supreme Court. The gateway to Strasbourg is open once all domestic remedies have been exhausted (Art 35 of the ECHR). Whether it is always worthwhile entering those gates is another matter.
(The National Council of Civil Liberties) v The Government
Communications Headquarters and Others  UKIPTrib 13_77-H (05
Amnesty - Historic victory with today's GCHQ surveillance ruling