The Signal Messenger app is displayed on a smartphone in Hong Kong, China.
Roy Liu | Bloomberg | Getty Images
Federal investigators say they accessed encrypted signals messages sent ahead of the Jan. 6, 2021 riots at the US Capitol and used them as evidence to indict the leader of the Oath Keepers, an extremist far-right militia group. and other accused in a seditious conspiracy.
In a new legal complaint released Thursday, the Justice Department found alleges the defendants conspired to violently reverse the transfer of power between then-President Donald Trump and Joe Biden, including by attempting to seize control of the US Capitol.
The complaint relates to numerous messages sent via Signal, an end-to-end encrypted messaging app that raises questions about how authorities accessed it and a longstanding point of tension between the law enforcement community and the tech industry remind. Encryption scrambles messages so that no one but the intended recipients can read them — including the platform hosting the messages.
It’s unclear how investigators got the news. Representatives from Signal, the Justice Department and the Federal Bureau of Investigation did not immediately respond to CNBC’s requests for comment.
One possibility is that another recipient with access to the messages turned them over to investigators. The complaint relates to group messages running in the app, so another participant in those chats may have cooperated.
Encryption has been a point of contention between investigators and tech companies for years. While law enforcement fears criminals are exploiting encrypted technology to conceal wrongdoing, technology companies like Apple have argued that it’s an important privacy tool. Law enforcement agencies have tried in the past to get tech companies to open up their devices to help investigate serious crimes, but companies like Apple argue that cracking encryption for US investigators will compromise the entire system and potentially leaving room for foreign opponents to exploit weaknesses.
The issue received particular attention in 2015 when Apple refused to crack the encryption on a suspect’s iPhone after a mass shooting in San Bernadino, California. After a tense standoff, investigators were finally able to crack the encryption themselves.
But some law enforcement agencies have said that newer iPhone software security features now make it more difficult for them to technically access those devices, even if they’re able to obtain a search warrant.
The problem resurfaced under the Trump administration, including when Meta, then known as Facebook, announced plans to tie all of its messaging services together and encrypt them end-to-end. Law enforcement officials said the plans would limit their ability to crack down on child sex abuse material on the platform.
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