스마트 컨트랙트에 대한 규제 개선 방안 - Van Loon v. Department of Treasury 판결의 시사점을 중심으로 -

In Van Loon v. Department of the Treasury, No. 23-50669 (5th Cir. 2024) (the “Van Loon”), the U.S. Court of Appeals for the Fifth Circuit stated that the immutable smart contracts of the virtual-asset mixing protocol Tornado Cash cannot be interpreted as “property,” “contracts,” or “services” subject to sanctions under the International Emergency Economic Powers Act (IEEPA). Accordingly, the Office of Foreign Assets Control (OFAC)’s designation of Tornado Cash on the Specially Designated Nationals and Blocked Persons List (SDN List) and the associated blocking sanctions were ultra vires because the agency treated the immutable smart contracts as “property in which a foreign country or a national thereof has any interest.” The Van Loon is notable in the wake of Loper Bright Enterprises v. Raimondo, 603 U.S. 369 (2024), in which the Supreme Court overruled Chevron Deference. The Fifth Circuit interpreted IEEPA de novo rather than deferring to OFAC, stating that Tornado Cash’s immutable smart contracts lack the ordinary features of property: the capacity for ownership, the right to exclude others, and the rights of possession and control. The concept of “property” in IEEPA’s 1977 enactment cannot readily address blockchain’s technical features—such as decentralization and non-modifiable code—so a tailored regulatory framework aligned with technological innovation is needed. The implications extend beyond administrative law: a comprehensive analysis of civil, financial, and constitutional law is required, and these implications are equally pertinent to Korea. Korea has sought to bring virtual assets within its regulatory frameworks through the Act on Reporting and Use of Specified Financial Transaction Information and the Virtual Asset User Protection Act. However, regulatory frameworks for decentralized protocols remain underdeveloped. (ⅰ) Because traditional regulatory frameworks are ill-suited to the immutable smart contracts, regulators should design technology-congruent, specialized regimes. This entails clarifying their status under civil law and the applicability of contract law, while considering narrow exception clauses, specialized arbitration procedures, and independent code-audit mechanisms that reflect their distinctive technical features. (ⅱ) As the immutable smart contracts are tools and are not proper targets of sanctions, the discussion should focus on developer liability tied to purpose and intent; legislative refinements should incorporate factors such as technical ownership, effective control, and modifiability as criteria for differentiated regulation to preserve judicial remedies. (ⅲ) For the immutable smart contracts, indirect approaches—such as regulating the design and deployment phases and intermediary services—are warranted. This includes gatekeeper obligations, a risk-based approach, and regulatory sandboxes. (ⅳ) To safeguard freedom of expression, regulators should distinguish between code creation/distribution and illicit misuse, while ensuring remedial measures through emergency stop mechanisms, clear disclosures on ownership, control, and modifiability, and risk disclosures. The law should also specify the responsible actors, the offense elements, and the scope and limits of liability to satisfy the principles of legality and definiteness in criminal law.