On Tuesday, the European Court of Human Rights issued a pivotal ruling on mass surveillance that should have implications in the U.K. and beyond. The court found that plaintiffs Claudio Guarnieri and Joshua Wieder, both experts on data protection and surveillance, “reasonably” believed that the GCHQ, the U.K.’s main intelligence agency, had intercepted their data under its bulk data collection regime.

Guarnieri and Wieder originally brought their case to the U.K.’s Investigatory Powers Tribunal in 2016, in what amounted to a test of the system in the wake of the Edward Snowden revelations, which exposed the large-scale spy programs of not only the U.S., but also the U.K., Australia, Canada and New Zealand governments. When the Tribunal refused to hear their case, they took it to Strasbourg. Even though the two plaintiffs aren’t U.K. citizens, the court decided they still had some baseline rights to privacy under the European Convention on Human Rights.