The Tribunal is the only UK court with the power to oversee GCHQ, Mi5 and Mi6. This is the first time it has ever ruled against one of the intelligence and security services.
The court found that the intelligence sharing between the US and UK agencies prior to December 2014 was unlawful because the rules governing UK access to the NSA’s PRISM and UPSTREAM programmes were secret.
The existence of both programmes was not known until the release of documents disclosed by NSA whistleblower Edward Snowden. The case before the IPT was brought by Privacy International, Bytes for All, Liberty and Amnesty International.
➤ IPT ruling [PDF]