Attorney General Eric Holder announced last week that the federal government will no longer prosecute dispensers of medical marijuana if they comply with state law.
That should bring relief to people who need marijuana for health reasons and free up law enforcement resources for more important work.
There is considerable evidence that marijuana can be useful in treating pain, nausea, weight loss and other symptoms associated with chemotherapy and H.I.V. and other illnesses. Thirteen states, including California, have legalized marijuana for medical purposes, which remains illegal under federal law.
The Bush administration was, nevertheless, intent on stopping the medical use of marijuana. It brought criminal charges against medical marijuana dispensaries, even ones in states that had made medical use of marijuana legal. Federal prosecutors treated their targets like common drug traffickers.
In 2006, the Food and Drug Administration issued a poorly documented statement disputing marijuana’s therapeutic value. It was one of many cases in which the Bush team distorted science to justify its policies.
Mr. Holder’s statement does not mean an end to all medical marijuana prosecutions. The Drug Enforcement Administration says it will continue to go after dispensaries that violate state and federal laws, like by operating as fronts for drug dealers or selling to minors.
The Obama Justice Department has an enormous backlog of legal matters to work through, from enforcing long-ignored civil-rights laws to prosecuting white-collar criminals in the banking industry and on Wall Street. Mr. Holder deserves credit for recognizing that going after medical marijuana dispensers is not only bad policy, it is a distraction from work that really matters.