This post has been updated.
The government refused again Thursday to allow the use of marijuana for medical purposes, reaffirming its conclusion that the drug’s therapeutic value has not been proved scientifically and defying a growing clamor to legalize it for the treatment of a variety of conditions.
In an announcement in the Federal Register and a letter to petitioners, the Drug Enforcement Administration turned down requests to remove marijuana from “Schedule I,” which classifies it as a drug with “no currently accepted medical use” in the United States and precludes doctors from prescribing it.
