A federal judge in California declined Wednesday to remove marijuana from the list of most dangerous drugs.
U.S. District Judge Kimberly Mueller issued the ruling in response to a motion by defense attorneys to dismiss charges in a case that authorities say involves a marijuana growing operation. It will likely be appealed.
The case was unusual in that Mueller decided to consider marijuana's designation as a Schedule 1 drug. Schedule 1 drugs include heroin and LSD and are defined as drugs with no accepted medical use and a high potential for abuse.
Marijuana's classification as a Schedule 1 drug has brought states that have legalized medical marijuana into conflict with federal authorities, leading to raids on growers and dispensaries that appear to be operating legally under state law.
Mueller said during a 15-minute court hearing that she was initially prepared to grant the defense's motion but then decided from the facts of this particular case that "this is not the court and this is not the time."
She said a written ruling would be issued by the end of the week.
Attorneys for the defendants had argued that marijuana was far less harmful than legal drugs, and its classification as a Schedule 1 drug was arbitrary in violation of the Constitution. They also said the government enforced marijuana laws unevenly, allowing its distribution in states that have legalized it while cracking down elsewhere.
Prosecutors said marijuana met all the criteria for a Schedule 1 drug, saying it has no accepted medical use and a high potential for abuse. They also argued that Mueller did not have jurisdiction to consider how marijuana was classified.
Mueller held a fact-finding hearing about the drug's classification last year that included prosecution and defense experts who testified about marijuana.
The criminal complaint filed in 2011 named 16 defendants and accused them of conspiring to grow at least 1,000 pot plants as part of a marijuana operation that included land in Shasta-Trinity National Forest in California.