When alcohol Prohibition was lifted in 1933, regulation was left to the states. Oklahoma stayed dry until 1959, Mississippi until 1966.

Bonnie said he sees marijuana legalization advocates leaning toward a similar model. But, he warns, "there is a social cost to a regulatory regime that taxes and becomes dependent on the revenue."

Overtax it, and you create another dilemma: black markets and the smuggling of marijuana from state to state, a la post-Prohibition. Canada and Sweden learned that lesson with cigarette taxes in the 1990s.

All of this is putting the roach before the joint, of course. Marijuana, no matter what Colorado and Washington say, remains illegal at the federal level.

Experts are reluctant to forecast when that might change. Aldrich predicts federal legalization by 2017, but he concedes that in 1969 he predicted the federal government would relent by 1979.

Judge Kane said he foresees marijuana following a similar path as alcohol. Toward the end of Prohibition, judges wantonly dismissed violations or levied fines so trivial that prosecutors quit filing cases, he said.

While he sees marijuana laws that target kingpins, traffickers and those who engage in violence remaining in place, he believes possession laws are endangered, he said.

"The law is simply going to die before it's repealed. It will just go into disuse," Kane said. "It's a cultural force, and you simply cannot legislate against a cultural force."