Now, that debate is set to rage once more with the US and its intelligence allies issuing an ultimatum to tech companies worldwide: give us access to encrypted data and devices, and if you don't, we'll force you.
Government representatives from the US, UK, Canada, Australia and New Zealand — the so-called "Five Eyes" intelligence community — met in Australia last week to discuss to the future of cybersecurity, national security and the growing threat of terrorism in digital spaces.
The Five Country Ministerial meeting (FCM) issued a number of joint statements, including a Statement of Principles on Access to Evidence and Encryption which came with a strong message: "privacy is not absolute."
The Statement reiterated governments and tech companies have a "mutual responsibility" to ensure access to "lawfully obtained data."
"Providers of information and communications technology and services — carriers, device manufacturers or over-the-top service providers — are subject to the law, which can include requirements to assist authorities to lawfully access data, including the content of communications," the statement read.
"Currently there are some challenges arising from the increasing use and sophistication of encryption technology in relation to which further assistance is needed."
It's a bullish statement, and could mean that everyone from hardware manufacturers like Apple and Samsung to service providers like Facebook, Google and WhatsApp could be forced to "assist" in giving access to communications on their platforms.
The battle over encryption is not new. While governments and intelligence agencies say they need access to encrypted communications in order to police crimes like child exploitation and terrorism, tech companies and digital rights advocates say opening so-called "back-doors" into encrypted communications has the potential to decrease security and privacy for everyone. And often, it's simply not possible.
But that hasn't stopped the Five Eyes powers calling on tech companies to "voluntarily" build features into their hardware and software to allow law enforcement to get an easy way in.
And if they don't?
"Should governments continue to encounter impediments to lawful access to information necessary to aid the protection of the citizens of our countries, we may pursue technological, enforcement, legislative or other measures to achieve lawful access solutions."
That's a big stick to wield at tech companies who (if Apple is anything to go by) are particularly reticent to hand over their customers' information.
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But the issue isn't going away. The back-and-forth between Apple and the FBI was just the start in recent years, with some US members of congress recently proposing laws that would stop the government forcing companies to decrypt communications. The UK has also struggled with the issue in light of a spate of terror attacks, with Prime Minister Theresa May calling on tech companies to "do more" to assist law enforcement.
The communiqué released out of the Australian meeting also follows proposals from the Australian government to introduce laws that would require tech companies to build capabilities into their tech to open access to data. But Australian leaders say the laws would "expressly prevent" the creation of back doors.
Apple did not immediately respond to a request for comment.
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