Roman Storm, founder of the Tornado Cash privacy tool, has warned that open-source developers may face retroactive criminal risk from US prosecutors for building non-custodial finance software.
His message has echoed through the crypto community as his own legal fight moves forward. Reports have disclosed a mixed jury outcome in Manhattan and a high-stakes debate over whether publishing code can amount to running a money-transmitting business.
Storm asked DeFi developers: “How can you be so sure you will not be charged by the Justice department as a money service business for building a non-custodial protocol?”
Developers Warned Of Retroactive Risk
According to court filings and public statements, Storm argued that US law gives little protection to people who publish software that others use to move funds. Based on reports, prosecutors called Tornado Cash a system that had been used to launder more than $1 billion.
Just a question for current DeFi devs:
How can you be so sure you won’t be charged by the DOJ as an MSB – for building a non-custodial protocol – and then accused you should’ve built it custodial instead?
If SDNY can charge a dev for building a non-custodial protocol…
who’s…— Roman Storm
(@rstormsf) October 18, 2025
Storm’s team pushed back, saying the protocol was non-custodial — the software does not hold user funds — and that blaming builders for users’ crimes would chill honest open-source work.
Tornado: A Jury Split Over Charges In Manhattan
The jury could not reach agreement on other, more serious counts. The US Attorney’s Office had described broad illicit use of the tool, while the defense has focused on the technical facts: no single person controlled the protocol in the way a bank controls accounts.
Defense lawyers have filed motions seeking acquittal and asked judges to weigh whether code creators can be punished for how third parties use their work.
Legal Community Raises Alarm
Based on reports, lawyers and commentators, including noted crypto legal experts, warn that the case could set a wide precedent if prosecutors’ theory holds.
Some in the community have organized fundraising to help with the Tornado Cash founder’s legal costs. Others say the matter touches free speech, since publishing code can be a form of expression, and holding authors criminally liable would change how many people write and share software.
Defense Moves And Technical Arguments
Storm’s team points to decentralization and noncustodial design. They argue that the protocol’s code runs on public blockchains and that no person was operating a service that took custody of funds in the ordinary sense.
Recent court filings press these themes and ask the judge to overturn the guilty verdict. Prosecutors counter that when tools are built and promoted in ways that foresee illicit use, legal responsibility can follow.
Featured image from TechCentral, chart from TradingView
