TechScape: What should social media giants do to protect children?

In this week's newsletter: UK cybersecurity heads want companies like Apple to monitor suspicious activity on devices. It's not the attack on privacy you might think it is

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This week, the technical leads of GCHQ and the National Cyber Security Centre made a powerful intervention into an incredibly controversial debate: what should social media companies do to protect children on their platforms?

But that wasn't how the intervention was taken by all parties. Others heard something rather different: tired arguments against end-to-end encryption, dressed up in new clothes but disguising the same attack on privacy rights with the same excuse that's always wheeled out by law enforcement.

Tech companies should move ahead with controversial technology that scans for child abuse imagery on users' phones, the technical heads of GCHQ and the UK's National Cyber Security Centre have said.

So-called client-side scanning" would involve service providers such as Facebook or Apple building software that monitors communications for suspicious activity without needing to share the contents of messages with a centralised server.

Apple is taking a major step into the unknown. That's because its version of this approach will, for the first time from any major platform, scan photos on the users' hardware, rather than waiting for them to be uploaded to the company's servers.

By normalising on-device scanning for CSAM [child sexual abuse material], critics worry, Apple has taken a dangerous step. From here, they argue, it is simply a matter of degree for our digital life to be surveilled, online and off. It is a small step in one direction to expand scanning beyond CSAM; it is a small step in another to expand it beyond simple photo libraries; it is a small step in yet another to expand beyond perfect matches of known images.