Objective: To highlight how sourcing practices for lethal injections drugs are undermining state and federal regulatory structures established to preserve the security and integrity of the medicines supply chain in the United States.Summary: Unable to find sources for execution products approved by the U.S. Food and Drug Administration (FDA), some states have started sourcing the required drugs or active ingredients from unapproved foreign manufacturers or have contracted with small compounding pharmacists to compound them. Many states have passed legislation barring the disclosure of information regarding the origin and chain of custody for prisons' stocks of compounded lethal injection drugs. This creates a regulatory vacuum and prevents the responsible authorities (e.g., FDA, Drug Enforcement Agency, state boards of pharmacy) from performing their crucial roles to ensure quality and supply chain transparency for medicines in circulation.Conclusion: By purchasing medicines from non–FDA-approved suppliers and enacting lethal injection sourcing secrecy laws, states are undermining the robust enforcement of chain of custody and pharmaceutical supply chain transparency. The secrecy surrounding the execution drug procurement risks creating illicit supply channels. Once an illicit supply channel is established with a supplier, it creates risks that other drug products move through it, particularly in a context where the FDA, Drug Enforcement Agency, and state boards of pharmacy are prevented from performing their usual regulatory duties. Lawmakers have the obligation and authority to step in and close this regulatory gap to promote public health and safety.