Matthew Green publishes code for sanctioned Tornado Cash on GitHub

Many people were startled when the United States Treasury Department’s Office of Foreign Assets Control (OFAC) decided to add the well-known Ethereum-based crypto mixer Tornado Cash as an entity on the Specially Designated Nationals (SDN) sanction list.

An uproar from privacy and free speech supporters was triggered by the later deletion of its source code from the Microsoft-owned GitHub, which also resulted in the termination of the user accounts of three people who contributed programming to the project.

Tornado Cash code on GitHub once again

While versions of the open source code for Tornado have continued to exist on GitHub, Johns Hopkins University professor of cryptography Matthew Green published another fork of the code this week with assistance from the Electronic Frontier Foundation (EFF).

Kurt Opsahl, a fellow member of the EFF, and Green had criticized the removal of Tornado Cash’s source code from Github and claimed that the action had stifled speech.

The primary intent of the Tornado Cash code’s re-upload is to see if ever removing it is the proper response to sanctions. Improvements and other contributions to this fork, or any other, are protected speech, and the authorities cannot lawfully ban their publication under either standard of scrutiny, according to Opsahl, who also happens to be the EFF’s general counsel.

Green echoed this attitude and stated that the advocacy group intended to take GitHub to court if the feature is ever again disabled. The researcher explained:

“In my work as a researcher and instructor at Johns Hopkins, I’ve made extensive use of the Tornado Cash and Tornado Nova source code to teach concepts related to cryptocurrency privacy and zero-knowledge technology.”

Notably, Kraken CEO Josse Powell also questioned the ban’s legitimacy and expressed doubts about whether the decision would hold up to judicial review.

Moreover, the non-profit advocacy organization called Coin Center recently is planning to file a lawsuit against the US government for its “unconstitutional” decision against the mixer.