A secret legal regime that governs mass surveillance by the UK intelligence agencies does not breach human rights, a tribunal ruled today.

The decision by the Investigatory Powers Tribunal (IPT), which oversees the intelligence agencies, is part of a legal challenge brought by Amnesty International, Privacy International, Liberty and other groups.

The organisations claim, on the basis of revelations by US whistleblower Edward Snowden, that their communications may have been monitored and that information obtained by the US National Security Agency (NSA) may have been shared with British intelligence services.

Before examining whether or not the groups’ communications had actually been intercepted, the tribunal looked at whether the legal regime governing the government’s surveillance practices were compliant with the Human Rights Act.

Amnesty and the other groups argued that because the government’s policies on interception were secret, the regime did not comply with transparency requirements under the act.

In October, as a result of the case, the government disclosed a 1.5 page summary of its policies and procedures. The document revealed that GCHQ does not need a warrant in order to receive bulk data from the NSA and other foreign agencies.

The summary also suggested that data received from foreign intelligence agencies is not subject to safeguards that applied to communications intercepted by the UK government.

But in its ruling today, following closed discussions of the government’s internal policies and procedures, the tribunal found that the legal regime is adequate to protect the public.

“The ‘Snowden revelations’ in particular have led to the impression voiced in some quarters that the law in some way permits the intelligence services carte blanche to do what they will,” the tribunal judgment said. “We are satisfied that is not the case.”

If the agencies were to indiscriminately trawl for information by interception or ask “another state to do what they could not lawfully do themselves” they would be breaking the law, it added.

The IPT also ruled that the government’s policies and procedures on interception do not have to be publicly available in full in order to comply with the transparency requirements of human rights law.

By disclosing the 1.5 page document, the government had met these requirements, it said.

In a small concession to the claimants, the tribunal left open to further argument the possibility that prior to the release of the document, the regime had not been compliant.

Nick Williams, counsel for Amnesty International, said this “very limited weakness” was a “red herring”.

“The wider regime has massive and substantive weaknesses across the board – for example, the ability of government to sweep up meta data and use and analyse that without safeguards,” he said.

The government has continued to publicly neither confirm or deny the surveillance practices revealed by Snowden so the tribunal judgement was made on the hypothetical basis that these practices existed.

However the IPT refused to hear arguments on the same hypothetical basis about whether such surveillance is proportionate.

It said it would only consider the issue of proportionality in relation to the individual cases.

The tribunal is now expected to look at whether the groups’ communications were actually intercepted and if so, whether this was done on a legal and proportionate basis.

This will be done in closed sessions and the groups will only be told the outcome if a breach of procedure is uncovered.

The claimants plan to take their challenge to the legality of the regime to the European Court of Human Rights, as IPT decisions cannot be appealed in the UK.

Earlier this year the Bureau of Investigative Journalism challenged the government’s surveillance practices on the grounds that journalists’ sources and communications are inadequately protected from government scrutiny and mass surveillance.