NEW YORK — Roman Storm, the Tornado Cash developer standing trial in Manhattan on charges that the privacy tool he created helped hackers and other cyber criminals launder more than $1 billion in criminal proceeds, won’t take the stand, his lawyers told the court on Tuesday.

Storm told District Judge Katherine Polk Failla of the U.S. District Court of the Southern District of New York (SDNY) that he was aware that he had the right to testify in his own defense but chose not to. After Storm made his decision, his defense team, led by Keri Axel and Brian Klein of Waymaker LLP, rested their case on Tuesday afternoon.

Over three days of witness testimony, the defense argued that Storm was merely the developer of a legitimate privacy tool that was sometimes exploited by bad actors – something which he and his co-founders could do little to actually stop, because the Tornado Cash protocol and its pools were immutable. While Storm and the other Tornado Cash co-founders made money from the sale of TORN tokens, they didn’t profit directly from Tornado Cash, witnesses testified. And, though prosecutors attempted to portray Storm and his co-founders as indifferent — even callous — to the plight of hack victims whose money was laundered through Tornado Cash, witness testimony, group chats and messages showed that Storm and his co-founders were unhappy with hackers using their platform.

In messages between Storm and his co-founder, Roman Semenov (who also faces the same charges and remains at large), Storm expressed concern in the wake of major hacks, including the 2022 hack of Ronin Bridge, in which North Korean hackers stole $600 million and funneled a portion of the proceeds through Tornado Cash. In the chat, Storm and Semenov discussed adding the hackers’ wallet to the Tornado Cash user interface’s blocked list.

“We urgently need to tell everyone we do not want these individuals to the front,” Storm told Semenov.

In another string of messages following the Ronin Bridge hack, Storm told Semenov that the hackers’ use of Tornado Cash was “very serious.”

After the 2022 hack of the Harmony Horizon Bridge, in which some proceeds flowed through Tornado Cash, Storm — messaging with Haseeb Qureshi, managing partner at crypto venture capital firm Dragonfly Capital that invested almost $1 million in Tornado Cash parent PepperSec Inc. — said: “I’m glad those fuckers are detected.”

Value of privacy

Storm’s defense elicited witness testimony detailing non-criminal reasons why someone might want to use a tool like Tornado Cash to separate their identity from their financial transactions.

Dr. Matthew Green, renowned cryptography expert and professor of computer science at Johns Hopkins University, told the jury on Tuesday that the lack of privacy was a “bug” in the majority of cryptocurrencies, exposing users to threats from hackers and other attackers.

Green — who offered his expert witness services to Storm’s defense for free — explained that, without a tool like Tornado Cash, Ethereum users are exposing sensitive personal information with every transaction, including how much money they have, what they spend it on and who they associate with. This presents a range of security risks, including phishing attempts, fraud and in-person “wrench attacks,” which Green explained have been “accelerating” in recent years.

Next steps

Whether the jury will side with the prosecution’s view of Tornado Cash or the defense’s has yet to be decided.

Tomorrow, both sides will have a chance to summarize their arguments in closing statements to the jury, after which the jury will be instructed by the judge on the charges against Storm and then released to deliberate.