Backdoors That Let Cops Decrypt Messages Violate Human Rights, EU Courts Says

February 15, 2024 TH Author headline,government,privacy,phone,backdoor

Enlarge / Building of the European Court of Human Rights in Strasbourg (France).

The European Court of Human Rights (ECHR) has ruled that weakening end-to-end encryption disproportionately risks undermining human rights. The international court’s decision could potentially disrupt the European Commission’s proposed plans to require email and messaging service providers to create backdoors that would allow law enforcement to easily decrypt users’ messages.

This ruling came after Russia’s intelligence agency, the Federal Security Service (FSS), began requiring Telegram to share users’ encrypted messages to deter “terrorism-related activities” in 2017, ECHR’s ruling said. A Russian Telegram user alleged that FSS’s requirement violated his rights to a private life and private communications, as well as all Telegram users’ rights.

The Telegram user was apparently disturbed, moving to block required disclosures after Telegram refused to comply with an FSS order to decrypt messages on six users suspected of terrorism. According to Telegram, “it was technically impossible to provide the authorities with encryption keys associated with specific users,” and therefore, “any disclosure of encryption keys” would affect the “privacy of the correspondence of all Telegram users,” the ECHR’s ruling said.

For refusing to comply, Telegram was fined, and one court even ordered the app to be blocked in Russia, while dozens of Telegram users rallied to continue challenging the order to maintain Telegram services in Russia. Ultimately, users’ multiple court challenges failed, sending the case before the ECHR while Telegram services seemingly tenuously remained available in Russia.

The Russian government told the ECHR that “allegations that the security services had access to the communications of all users” were “unsubstantiated” because their request only concerned six Telegram users.

They further argued that Telegram providing encryption keys to FSB “did not mean that the information necessary to decrypt encrypted electronic communications would become available to its entire staff.” Essentially, the government believed that FSB staff’s “duty of discretion” would prevent any intrusion on private life for Telegram users as described in the ECHR complaint.

Seemingly most critically, the government told the ECHR that any intrusion on private lives resulting from decrypting messages was “necessary” to combat terrorism in a democratic society. To back up this claim, the government pointed to a 2017 terrorist attack that was “coordinated from abroad through secret chats via Telegram.” The government claimed that a second terrorist attack that year was prevented after the government discovered it was being coordinated through Telegram chats.

However, privacy advocates backed up Telegram’s claims that the messaging services couldn’t technically build a backdoor for governments without impacting all its users. They also argued that the threat of mass surveillance could be enough to infringe on human rights. The European Information Society Institute (EISI) and Privacy International told the ECHR that even if governments never used required disclosures to mass surveil citizens, it could have a chilling effect on users’ speech or prompt service providers to issue radical software updates weakening encryption for all users.

In the end, the ECHR concluded that the Telegram user’s rights had been violated, partly due to privacy advocates and international reports that corroborated Telegram’s position that complying with the FSB’s disclosure order would force changes impacting all its users.

The “confidentiality of communications is an essential element of the right to respect for private life and correspondence,” the ECHR’s ruling said. Thus, requiring messages to be decrypted by law enforcement “cannot be regarded as necessary in a democratic society.”

The ruling “strikes a blow to authoritarian measures that seek to undermine fundamental rights protections in the digital age,” Ioannis Kouvakas, senior legal officer for Privacy International, told Ars. “By finding that Russia’s efforts to circumvent encryption of online messaging services violated the European Convention on Human Rights, the Court sends a clear message to other governments currently toying with similar ideas: risking the privacy and security of each and every user is certainly not the way to go.”

Martin Husovec, a law professor who helped to draft EISI’s testimony, told Ars that EISI is “obviously pleased that the Court has recognized the value of encryption and agreed with us that state-imposed weakening of encryption is a form of indiscriminate surveillance because it affects everyone’s privacy.”