Most Americans now think that marijuana should be legalized. A new paper for the Brookings Institution by Bill Galston and E.J. Dionne draws attention to this startling shift of public opinion: Support for legalization has surged by almost 20 percentage points in less than a decade and by 11 points in the past three years.

According to recent polling by the Pew Research Center for the People and the Press, 52 percent of Americans favor legalization. Just 20 years ago, 80 percent of Americans opposed it. Note that these figures are for outright legalization. (Support for legalizing the medical, as opposed to recreational, use of marijuana is far stronger: 77 percent are currently for it.) Seven years ago, 50 percent of Americans thought that using marijuana was immoral; that has dropped to 32 percent.

This dramatic shift has already led to successful ballot initiatives to legalize recreational use of the drug in Colorado and Washington state, and more such measures are on the way.

It's tempting to draw a parallel with the abrupt change of opinion on gay marriage and to think that a once-and-for-all generational shift lies behind both -- but, as Galston and Dionne point out, it isn't so simple. Generational differences are decisive in the case of gay marriage, making it hard to imagine that attitudes could ever shift back. Attitudes on the legalization of marijuana are more tentative.

For example, many of those who support legalization do so despite believing that the drug is harmful -- polling confirms that they see the consequences, rather than the goal, of the current control system as the main problem. The public is weighing costs and benefits. Support for reform is therefore qualified (and less intense than opposition to legalization).

Here's the crucial number. More than 70 percent think that "government efforts to enforce marijuana laws cost more than they are worth." This wide margin of disapproval of the current system unites every demographic segment of U.S. society. Every ideological segment too: Large majorities of Republicans, Democrats, independents, conservatives, liberals and moderates all think the current costs of enforcement outweigh the benefits.

Yet legalization remains to be tested. "Whether opinion swings toward more robust support for legalization," the authors write, "will depend heavily on the perceived success of the state legalization experiments now under way -- which will hinge in part on the federal response to those experiments."

This raises some interesting questions. One is whether reformers might come to see outright legalization, rather than the milder option of decriminalization, as a mistake.

Decriminalization, popular in Europe and already adopted in parts of the U.S., leaves laws prohibiting marijuana mostly in place but eases enforcement. Possession of small amounts of the drug isn't prosecuted, and users don't face imprisonment -- which avoids the heaviest costs of the "war on drugs." Also, according to some researchers, mere decriminalization doesn't promote use of the drug, whereas full legalization might, because it lets producers commercialize the product. Decriminalization has drawbacks too, of course. It's hard to justify a prohibition you aren't willing to enforce, and if you don't legalize the drug, you can't easily regulate or tax it.

The party politics of the change in sentiment are worth pondering, too. Democrats support legalization 59-39 percent, and Republicans oppose it 60-37 percent. But, as just noted, Republicans agree that the costs of enforcing the prohibition outweigh the benefits. Also, Republicans agree with Democrats that the federal government shouldn't enforce federal prohibition in states that have decided to legalize. The partisan margins on this are similar: Republicans oppose a federal override of state-level legalization 57-40, Democrats 59-35.

Apparently the Republican position on states' rights isn't, as the authors put it, "mere rhetoric" -- it takes precedence over the party's attitude to legalization. Ken Cuccinelli, Republican candidate for governor of Virginia, surprised students at the University of Virginia earlier this year when he was asked about legalization in Colorado and Washington and said, "I don't have a problem with states experimenting with this sort of thing. I think that's the role of states."

Intriguing, don't you think? Marijuana might bridge the partisan divide.

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To contact the author on this story:
Clive Crook at