Human rights and civil liberties organisations Amnesty International, Liberty and Privacy International have filed a joint application at the European Court of Human Rights challenging the government's mass surveillance practices.

The groups assert that domestic law governing the UK intelligence agencies' interception of communications and its intelligence sharing with the US, are in breach of fundamental human rights to privacy, freedom of expression and non-discrimination guaranteed under the European Convention on Human Rights. The challenge is based on documents disclosed by NSA leaker Edward Snowden revealing mass surveillance practices by intelligence agencies.

The suit filed with the ECHR is a response to a December ruling of the Investigatory Powers Tribunal which found that mass surveillance of internet traffic by tapping fibre optic cables going in and out of the UK and intelligence sharing between the US and the UK was lawful in principle and did not violate human rights.

The schemes were found to be legal because the government disclosed parts of secret policies used to govern these surveillance programs. As they were made public, the court found that the surveillance was compliant with human rights. In a follow-up ruling in February this year though, the tribunal ruled that the sharing of mass surveillance data between US and UK intelligence services was unlawful before December 2014, as the policies governing these processes were secret.

However, the groups said, mass spying has major consequences for people's privacy and freedom of expression and it is ridiculous that the government has been allowed to rely on secret policies.

Mass surveillance is illegal and intercepting communications of millions of people every day is neither necessary nor proportionate, they said, adding that no-one is above the law and the ECHR should make that clear.

The groups originally filed their complaint over mass surveillance in the UK in July 2013, and first had to exhaust all legal options in the UK before they could move the case to the human rights court.