The European Court of Human Rights (ECHR) on Thursday ruled that UK’s bulk interception powers, exposed by the whistleblower Edward Snowden, is illegal.

In a landmark judgment, the court ruled agencies had violated rights as there were no proper safeguards.

In 2013, Edward Snowden revealed that GCHQ – the UK’s eavesdropping agency – had been secretly collecting communications sent over the internet on an industrial scale. It could reassemble the communications, filter them and then analyze for targeted purposes – specifically, national security.

The agency could obtain data and content from its US partners and companies including Apple, Google and Facebook. The bulk surveillance revealed several aspects of the program. So-called “Karma Police” was aimed at documenting the web habit of internet users, “Tempora” was the bulk storage of all internet traffic GCHQ could harvest, and “Black Hole” was a digital library composed of more than one trillion internet events.

According to the judgment, there were no proper safeguards and unrelated personal information could be seen by GCHQ.

“While there is no evidence to suggest that the intelligence services are abusing their powers – on the contrary, the [then British watchdog] observed that the selection procedure was carefully and conscientiously undertaken by analysts, the court is not persuaded that the safeguards governing selection of bearers [internet cables] for interception and the selection of intercepted material for examination are sufficiently robust to provide adequate guarantees against abuse,” the judgment stated.

“Of greatest concern, however, is the absence of robust independent oversight of the selectors and search criteria used to filter intercepted communications.”

The court further flayed the powers to ask internet firms to hand over communications data, saying such data could reveal the identities and geographical location of the sender, recipient and the equipment used to transmit the communication.