¶Many people in treatment programs for marijuana are there because courts send them there as an alternative to incarceration; most judges know that people shouldn’t be jailed for smoking pot.

¶The vast majority of state medical marijuana laws were promulgated by legislatures, analyzed and affirmed by courts, and based on the advice of medical organizations representing the opinions of tens of thousands of physicians.

But, for the sake of argument, let’s say everything Mr. Evans says is true. What is he suggesting? Another 50 years of marijuana prohibition? It hasn’t worked; it’s now easier for children to buy pot than to buy beer. And billions of dollars are spent going after pot smokers instead of violent criminals.

GREG ANTON

Santa Rosa, Calif., Dec. 14, 2011

Scientists have long known that like many plants, marijuana has some medicinal properties. But that does not imply that to derive those medical benefits, the plant should be smoked in its raw form (we don’t, after all, smoke opium to get the benefits of morphine). Nor does the potential medical value of marijuana mean that, as medicine, its fate should be left to the whims of the electorate.

Unfortunately, rather than advocating better or quicker research protocols so that pharmacists can properly dispense marijuana-based medications with consistent dosing and in a safe delivery manner, many states have bypassed the approval process of modern medicine. The result has been widespread abuses.

The federal government could certainly speed up research into marijuana’s components by giving incentives to scientists who study the drug and loosening marijuana’s strict research requirements. But the current situation — characterized by the mass commercialization of marijuana and the proliferation of “rent-a-doctors” who indiscriminately hand out medical recommendations for the drug — places the truly sick at risk while detracting from the potentially promising future of properly approved marijuana-based medications.

KEVIN A. SABET

Honolulu, Dec. 14, 2011

The writer was an adviser on drug policy in the Obama, Clinton and George W. Bush administrations.