Germany must stand firmly against client-side scanning in Chat Control [pdf] (signal.org)

On October 3, 2025 Signal Foundation president Meredith Whittaker published a public warning urging Germany to resist reversing its opposition to the EU’s “Chat Control” proposal, which would mandate client-side scanning of every message, photo, and video on users’ devices. Framed as child protection, the policy would require devices to run government-mandated databases or AI models to classify content before or after encryption — effectively creating a universal surveillance layer. Signal calls the move “catastrophic,” arguing it would undermine the right to private communication that Germany has long defended. Technically, client-side scanning negates end-to-end encryption’s guarantees by introducing a trusted access point on users’ devices; attackers or hostile states could exploit that access rather than breaking strong crypto. The letter points to a broad technical consensus — and even warnings from intelligence agencies — that you cannot build a backdoor that only lets “good guys” in. Signal frames Chat Control as an existential threat: it would expand the attack surface for hacks, compromise officials, journalists and activists, and might force Signal to exit the market rather than embed surveillance into its app. Whittaker urges Germany’s Ministry of Justice to hold the line to protect privacy, national cybersecurity, and Europe’s long-term digital sovereignty.