The U.K. government’s secret order to Apple demanding it backdoor the end-to-end encrypted version of its iCloud storage service has now been challenged by two civil rights groups, Liberty and Privacy International, which filed complaints Thursday. They called the order “unacceptable and disproportionate” and warned of “global consequences” as the access order is thought to extend to non-U.K. users too.

The pair, along with two named individuals — Privacy International’s exec director Gus Hosein and the civil liberties advocate Ben Wizner — have instructed law firm Leigh Day to challenge Home Secretary
Yvette Cooper’s decision to serve Apple with a so-called Technical Capability Notice (TCN) under the Investigatory Powers Act (IPA). The existence of the secret order only emerged via press reports last month.

“Privacy International and Liberty fear this TCN, or similar TCNs in the future, could be used to undermine end-to-end encryption essential to the protection of privacy and free expression,” they write in a press release.

Apple has already filed a legal challenge to the TCN — and its appeal is due to be heard by the Investigatory Powers Tribunal (IPT), the body that oversees complaints against U.K. intelligence agencies. Both civil rights groups, Hosein, and Wizner contend that they are direct victims of the government’s TCN decision and are asked for their complaints to be joined to Apple’s.

They are also calling for the case to be heard in public, rather than behind closed doors — joining earlier calls from privacy rights groups. The IPT hearing is thought to be scheduled for today, Friday, March 14.