DEA will file formal written opposition to psilocybin administrative rescheduling by 2027-06-30, explicitly citing longitudinal safety data gaps or diversion risk.

The DEA (the US drug enforcement agency) will file an official written statement against moving psilocybin out of Schedule I (the strictest legal category) before June 2027. This matters because it's a powerful legal barrier that will slow or block any congressional or administrative push to reschedule the drug.

DEA has consistently opposed Schedule I reclassification absent full FDA approval. No national monitoring infrastructure exists for a Schedule III psychedelic. DEA's formal comment process (required under the CSA rulemaking procedure) will produce a documented, falsifiable written objection. This is distinct from mere inaction — it requires an affirmative filing. Resolves by checking DEA Federal Register submissions or official rulemaking record.