EFF: Code, Speech, and the Tornado Cash Mixer

EFF’s most central concern about OFAC’s [US Office of Foreign Assets Control] actions arose because, after the SDN [Specially Designated Nationals] listing of “Tornado Cash,” GitHub took down the canonical repository of the Tornado Cash source code, along with the accounts of the primary developers, including all their code contributions. While GitHub has its own right to decide what goes on its platform, the disappearance of this source code from GitHub after the government action raised the specter of government action chilling the publication of this code.

In keeping with our longstanding defense of the right to publish code, we are representing Professor Matthew Green, who teaches computer science at the Johns Hopkins Information Security Institute, including applied cryptography and anonymous cryptocurrencies. Part of his work involves studying and improving privacy-enhancing technologies, and teaching his students about mixers like Tornado Cash. The disappearance of Tornado Cash’s repository from GitHub created a gap in the available information on mixer technology, so Professor Green made a fork of the code, and posted the replica so it would be available for study. The First Amendment protects both GitHub’s right to host that code, and Professor Green’s right to publish (here republish) it on GitHub so he and others can use it for teaching, for further study, and for development of the technology.

EFF: Code, Speech, and the Tornado Cash Mixer