In their lawsuit, the communications providers claim that by allegedly interfering with network assets and computers belonging to the network providers, GCHQ has contravened the U.K. Computer Misuse Act and the European Convention of Human Rights (ECHR), which guarantees the individual's peaceful enjoyment of their possessions, they said.
Furthermore, conducting surveillance of the network providers' employees is in contravention of article 8 of the ECHR which covers the right to respect for private and family life, and article 10, which covers freedom of expression, they said. Surveillance of the network providers' users that is made possible by exploitation of their Internet infrastructure is also in contravention of those articles, the complainants said.
Moreover, by diluting the network providers' goodwill and relationship with their users, GCHQ could also have violated the ECHR, they added.
Privacy International already filed two other complaints with the Tribunal over the Snowden revelations. The first one was filed last July and concerns alleged mass surveillance on U.K. citizens via GCHQ's Tempora and the NSA's Prism program. A week-long public hearing for that case is set to begin on July 14, Rispoli said.
A second case was filed in May over GCHQ's and NSA's alleged ability to infect computers and mobile devices with malware, giving them control over the devices to switch on users' microphones or cameras, listen to phone calls and track locations. That case is still pending, Rispoli said.
Loek is Amsterdam Correspondent and covers online privacy, intellectual property, open-source and online payment issues for the IDG News Service. Follow him on Twitter at @loekessers or email tips and comments to email@example.com