Enforcement Speeds In DeFi: Limits to a Race Against Time

Abstract

Retrospective blacklist enforcement fails structurally in permissionless systems: adversaries create wallets offline at negligible cost while enforcement designates addresses on-chain at finite bandwidth, an asymmetry no improvement in investigation speed can resolve. We document this using the complete population of 173 OFAC-sanctioned Ethereum wallets. Across approximately $3.3 billion in total wallet value, we document two structural enforcement failures. First, approximately 71% of value, equivalent to approximately $2.4 billion, exits before designation. Second, around one-fifth of address-token pairs continue transacting after sanctioning, including autonomous smart contracts that cannot comply by design; for human-controlled wallets, the rate is around 8%. Only 1.47% of blacklisted balances remain frozen. A race-condition model shows these failures are architectural rather than operational: the investigation window gives adversaries a head start that no increase in investigation speed can eliminate, because wallet creation is free while enforcement is bandwidth-constrained. A second independent result shows that even zero investigation lag leaves enforcement incomplete due to computational complexity in transaction graph tracing.

Keywords: Anti-Money Laundering, Blockchain Regulation, Decentralized Finance, Sanctions Enforcement, Regulatory Compliance JEL Classification: G28

JEL Classification: G28, K22, K42, F38, O33