The law is the law. If we unquestioningly accepted that maxim, imagine where we would be today. Jim Crow would be alive and well, rivers and skies would be polluted, and women wouldn’t be allowed to vote.

Yet such is the mindset of many of those who criticize Proposition 19, the marijuana regulation and taxation initiative on the November ballot. In his July 18 Times Op-Ed article, UCLA public policy professor Mark A.R. Kleiman declares that state legalization “can’t be done.” He points out, correctly, that if the initiative is successful, the federal marijuana prohibition laws will remain in place. What he assumes, incorrectly, is that federal agents will swarm into California, busting farmers and arresting distributors and shopkeepers, to say nothing of the garden stores that sell them equipment and supplies, the accountants who do their books and the municipal tax officials who delight in assessing and collecting the new tax revenues.

Kleiman might well have uttered, “The law is the law.”

But the law is neither absolute nor infallible, and that’s why Californians can — and should — legalize, regulate and tax marijuana-related commerce.

The federal-state dynamic concerning marijuana is not complicated. Under our system of federalism, both the states and the feds may prohibit commerce in marijuana, but neither is required to do so. Similarly, during alcohol prohibition (1920-33), commerce in alcoholic beverages was prohibited not only by federal law (the Volstead Act) but by the laws of most states. In 1923, New York repealed its state prohibition laws, leaving enforcement, for the remaining 10 years, entirely to the feds. California voters overwhelmingly did the same thing in 1932, one year before national prohibition was repealed.

Let’s think this through. If Proposition 19 passes, two important balls roll into the feds’ court. The first is that the sole responsibility and expense of enforcing marijuana prohibition will be shifted to them. After Nov. 2, marijuana “offenders” could be arrested only by federal agents, prosecuted only under federal law, and sentenced only to federal detention.

If the feds undertook this, cases involving simple possession cases and small-time marijuana businesspeople, usually relegated to state courts, would flood federal courthouses. But even with a drastic increase in funding for federal enforcement, such activity would barely put a dent in California’s marijuana trade, and would fail to stifle California’s policy change, as the federal government has failed to do since the first medical marijuana laws were passed 14 years ago. Moreover, justifying the invasion into a state’s province to undermine the will of the voters at such great expense to taxpayers would be highly questionable, especially in the current economic climate, not to mention a political climate that is at best lukewarm on prohibitionist policies.

The second ball is even more significant. Voter approval of Proposition 19 would shift to the feds the responsibility and burden of justifying marijuana prohibition in the first place. Now, the Washingtonians who have never questioned decades of anti-pot propaganda can explain to the people of California why we cannot be trusted to determine our state’s marijuana policies. Let them endorse the prohibition laws’ usefulness as a tool of oppressing minorities. Let them celebrate how minor marijuana violations cost people their jobs, their housing, custody of their kids, and entrap them permanently in vast criminal justice databases. Let them justify the utter hypocrisy of the legal treatment of alcohol and tobacco, as compared with the illegal treatment of marijuana. Let them tell us how many more people will have to be prosecuted and punished before marijuana is eradicated, how much that will cost, and where the money will come from.

Proposition 19’s success in November would put the feds in a quandary, yes, but it is a quandary of their own making. Unlike alcohol prohibition, which required a constitutional amendment, Congress could fix this easily with a simple amendment to the Controlled Substances Act allowing conduct legal under state law and respecting the right of states to regulate and tax the cannabis industry. After all, determining what is a crime is traditionally handled at the state level; indeed, federal prosecutions of drug possession make up a miniscule portion of overall drug arrests.

Instead of hewing to a misguided and unworkable federal hegemony in this area, encouraging innovation at the state level would be a more rational federal policy. And to be clear, legal scholars have long disagreed with Kleiman’s conclusion that the feds must and will intervene to try to quell state action in this area.

States need not shrink from countering federal policy on marijuana. California can show leadership in driving needed reforms, as it has before. In other words, the law need not be the law if you’re willing to stick your neck out. Cautious academics and politicized public employees will always embrace the status quo, joined by risk-averse politicians who misconstrue a lack of constituent “noise” on this issue as satisfaction with current law, not fear. But voters know better.

Not only can Californians regulate and tax marijuana, we should.

Hanna Liebman Dershowitz, an attorney in Los Angeles, is a member of the Proposition 19 legal subcommittee.