Roman Storm Trial Hinges on Privacy and Decentralization of Tornado Cash

The trial of Roman Storm, co-founder of the Ethereum-based privacy protocol Tornado Cash, took center stage as the defense highlighted the technology’s decentralized nature and its value in protecting user privacy. Storm is facing charges that include conspiracy to commit money laundering, conspiracy to violate sanctions, and operating an unlicensed money transmitting business. His defense has maintained throughout the trial that he cannot be held criminally liable for how others choose to use the protocol.

The defense team brought in a series of witnesses to emphasize that Tornado Cash was not inherently a tool for criminal activity. Guy Wuollet, a partner at a16z crypto, testified that his firm had considered investing in Tornado Cash in 2021 due to its strong privacy features and potential for future growth. Although a16z ultimately did not invest—citing uncertainty around profitability—Wuollet expressed continued support for the protocol. When pressed on the issue of criminal misuse of the blockchain, Wuollet likened the situation to a store not being responsible for crimes committed using it [1].

Omid Malekan, a professor at Columbia Business School, provided further context by disclosing his own use of Tornado Cash in 2021 to purchase an Ethereum Name Service (ENS) name. He did so to avoid drawing attention to his identity. His brief testimony underscored the practical privacy benefits of the protocol and drew immediate objections from the prosecution [1].

Economist Stephanie Hurder, who was paid $120,000 by the defense for her expert analysis, challenged the prosecution’s narrative on decentralization. She pointed out that the Tornado Cash DAO was “well-designed and active,” with a significant portion of TORN tokens allocated to the DAO treasury. Hurder also noted that the founders did not always exercise their voting power or directly control the relayer registry. Under further questioning, she acknowledged that the token distribution had become less decentralized over time, but stopped short of endorsing the government’s broader claims about the protocol’s role in criminal activities [1].

Matthew Green, a computer science professor at Johns Hopkins University and co-creator of the Zerocash protocol, was called to testify on the importance of privacy in digital systems. He described public blockchain transactions as a “huge bug” and drew comparisons to privacy tools like VPNs and credit-card tokenization. Green confirmed the immutability of Tornado Cash pools, but also acknowledged that the user interface, website, and relay registry could be modified. His testimony ended with an unresolved question from the defense about the feasibility of a user registry system proposed by a previous government witness [1].

As the trial concludes, the defense is preparing to deliver its closing arguments. The case has raised significant questions about the legal responsibility of protocol developers for how their technologies are used, and whether the decentralized nature of blockchain can absolve individuals from criminal liability in cases of misuse. The jury now awaits final arguments and instructions before delivering its verdict.

Source: [1] Roman Storm trial: Witnesses play up Tornado Cash privacy, decentralization (https://blockworks.co/news/roman-storm-trial-witnesses)