According to Cointelegraph, Samourai Wallet's legal team has accused federal prosecutors of withholding crucial advice from the U.S. Treasury Department's Financial Crimes Enforcement Network (FinCEN) regarding the necessity of a license for their crypto mixing service. In a letter dated May 5 to a Manhattan federal court, attorneys representing Samourai co-founders Keonne Rodriguez and William Hill revealed that FinCEN had informed prosecutors six months prior to charging the pair that the Samourai Wallet app did not qualify as a 'Money Services Business' requiring a FinCEN license. Despite this guidance, prosecutors proceeded to charge Rodriguez and Hill with operating an unlicensed money transmitting business and conspiracy to launder money in February 2024, arresting them in April of the same year.

The letter further alleges that prosecutors failed to disclose their discussions with FinCEN within the required timeframe, instead suppressing the information for over a year before revealing it on April 1, 2025. Samourai's mixing service, which blends cryptocurrency from multiple users to obscure its origins, has been accused by the government of facilitating over $2 billion in illegal transactions and enabling more than $100 million in money laundering activities linked to online black markets and scammers. Both Rodriguez and Hill have pleaded not guilty to the charges.

In their correspondence, Samourai's lawyers highlighted a call with Kevin O’Connor, chief of FinCEN’s Virtual Assets and Emerging Technology Section, and Lorena Valente from the Policy Division. An email from prosecutor Andrew Chan summarizing the call indicated that FinCEN suggested Samourai was not acting as a money services business because it did not take custody of cryptocurrency by possessing private keys. The email also noted that FinCEN had not reached a definitive conclusion on Samourai's status, suggesting that arguing the platform functionally controlled the crypto could be challenging for prosecutors.

Samourai's legal team has requested a court hearing to examine the circumstances surrounding the delayed disclosure and seek appropriate remedies. They have indicated plans to renew their motion to dismiss the charges, arguing that Rodriguez and Hill lacked fair notice and believed their actions were lawful. Both parties have requested additional time from the court to consider dismissing the case, following the Justice Department's recent rollback of crypto enforcement. Rodriguez and Hill's lawyers contend that if the government continues to pursue the case despite the Justice Department's directive, they will argue for dismissal based on FinCEN's guidance that Samourai was not a money transmitter requiring a license.