The U.S. cryptocurrency legislation process hits a critical institutional snag in the Senate. Four major law enforcement and oversight organizations, including the National District Attorneys Association, have jointly submitted an open letter to Biden administration officials, expressing strong compliance concerns over key provisions of the upcoming vote on the *Clarity Act*. The letter specifically targets Section 604 of the bill, known as the *Blockchain Regulatory Certainty Act* (BRCA), arguing that the immunity framework established by this section would create a regulatory vacuum, substantially hindering judicial investigations and prosecutions of illegal financial activities on-chain. Law enforcement agencies pointed out in the letter that the current text of the *Clarity Act* fails to establish rigid safeguards for digital asset custodians and matching entities equivalent to those in traditional financial institutions. If the current draft is passed, certain non-custodial crypto participants, decentralized protocol developers, and liquidity nodes would be exempt from critical "Know Your Customer" (KYC) and Anti-Money Laundering (AML) compliance reporting obligations. This demand has directly delayed the bill's timeline for entering full Senate floor debate, becoming the most contentious negotiation point between bipartisan lawmakers and crypto lobbying groups.