The organization announced the filing of the lawsuit today, arguing that an "expansive espionage regime appears to operate outside the rule of law, is irresponsible, and is neither necessary nor appropriate.
Of course you understand that they are referring to the case NSA and the collaboration of the US secret service with its British analogue, GCHQ. Recently, it was revealed that the two services were working together to watch huge amounts of data. The data collected by GCHQ reportedly sent to the US secret service for study by its analysts.
The lawsuit was filed with the Investigatory Powers Tribunal - an independent judiciary that is separate from the government and hypothetically unaffected.
The lawsuit is based on two key points.
Firstly, there is no legal framework within which it is possible to monitor the contact details of UK citizens, local secret services or people behind the NSA PRISM.
Second, and perhaps even more apt, is that GCHQ utilizes and stores "huge amounts of data" via submarine cables with the Tempora program.
"One of the basic principles of law in a democratic society is the accessibility and predictability of the law. If there is no way for citizens to know about the existence, interpretation or execution of a law, then the law is secret. And a secret law is not fair. This is a fundamental breach of the social contract, if the government acts in such an arbitrary way, "said Eric King, head of research Privacy International.