Certainly they bring up good points, but I think there are a few things they're overlooking.
First, they've essentially said that because the CSA doesn't "occupy the field", ergo it doesn't set the penal precedents of the United States, there are discrepancies between states in terms of drug laws. That's a rather large oversight, as the discrepancies are largely penal in nature, that is, they differ in the logistics of how much of a controlled substance is punishable by what means. Insomuch as the CSA dictates that certain substances are essentially verboten, so too do the states dictate what amount of a drug is punishable. However, on a very basic level, all states must inherently comply with federal drug law in order for their state level drug legislation to be in accord with the CSA.
Secondly, and more importantly, their interpretation of section 903 seems a bit flawed. What they've deduced is that because Congress can't control the state laws, that California can legalize marijuana regardless of federal law. What you and I have both concluded however, is that there are two clauses in the Constitution that would conflict with this idea. What this opinion fails to address, or really dissent from, is the principle that the CSA is a general outline of federal policy, that is laid out in order to facilitate various state governments in elucidating what justification a state needs to prosecute for the presence of drugs in one form or another. In order to do so, the state governments must, in turn, subscribe to the ideology that at a fundamental level, the enumerated drugs are, in essence, illegal. Should there be grounds for dissent, it would be at a federal, not state level, in accord with this principle. Additionally, the author has done a fairly good job of extrapolating a couple of state court cases out to the federal level, where the point he's trying to make has not been supported.
Really though, all of that is essentially lip-service in that I think both you and I, and really anyone with a basic understanding of the laws and precedents involved here understand that there are Constitutional issues that would render the proposition moot.
"Nine former DEA administrators are urging the Obama administration to challenge Proposition 19, California's marijuana legalization inititiative, if voters approve it in November. They argue that state legalization of marijuana would violate the Constitution's Supremacy Clause, which says "this Constitution, and the Laws of the United States which shall be made in Pursuance thereof...shall be the supreme Law of the Land." Since Prop. 19 conflicts with the federal Controlled Substances Act, they say, it is unconstitutional. "The Justice Department invoked the Supremacy Clause in the State of Arizona," says former DEA Administrator Peter Bensinger, "and in that case the laws weren't even in direct conflict."
Bensinger is talking about the Obama administration's challenge to the Arizona law that requires police to check the immigration status of people they encounter in the course of their work and establishes state penalties for immigration-related offenses such as failure to carry a green card. But while controlling the nation's borders is clearly a federal concern, controlling the intrastate production, distribution, and consumption of marijuana is not. Even allowing for the Commerce Clause casuistry that has blessed such invasions of local territory, Bensinger et al. are wrong in suggesting that states must criminalize any commodity that offends Congress. During alcohol prohibition—which, unlike drug prohibition, was rendered constitutional through the old-fashioned method of amending the Constitution—some states adopted their own drink-suppressing measures but did not necessarily enforce them, while others declined to approve local versions of the Volstead Act or ultimately repealed them. Bruce Fein, who served in the Justice Department during the Reagan administration and now serves on the advisory board of the pro-legalization group Just Say Now, explains:
Nothing in the Constitution requires a state to prohibit as a matter of state law and prosecution what the federal government has chosen to prohibit as a matter of federal law and prosecution. Proposition 19 leaves the power of the federal government to enforce federal prohibitions on marijuana trafficking or use unimpaired.
The DEA, of course, won't have the resources to arrest all the pot growers, sellers, and users in California, or even a substantial portion of them. But that does not mean it can conscript state law enforcement agencies to do its dirty work.
In January, when Los Angeles Times editorialists were making the same argument about state pot legalization that Bensinger et al. are raising now, Drug Policy Alliance attorney Tamar Todd set them straight."
"The legal argument sounds superficially plausible, especially since the Supreme Court, based on a ridiculously broad reading of the Commerce Clause, has upheld national marijuana prohibition, even as applied to purely intrastate cultivation and possession of the drug by patients who are permitted to use it under state law. But it is one thing to say that the federal government may arrest patients for growing or possessing medical marijuana. It is quite another to say that the U.S. Constitution requires every state to arrest those patients too, which is what these former narcs in chief are claiming. A system that required states to ape every aspect of federal law, permitting what Congress permits, prohibiting what it prohibits, and applying criminal sanctions accordingly, would obliterate the last vestiges of federalism. Commandeering state and local officials to enforce a ban on a product that Congress deems unacceptable, something that did not happen even during alcohol prohibition, which unlike marijuana prohibition was constitutionally authorized, cannot possibly be reconciled with the 10th Amendment: "The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people."
As for the claim that no one will pay taxes on marijuana because growing and selling it will still be a federal crime, it has already been proven false. California collects something like $100 million in sales tax revenue from medical marijuana dispensaries every year, even though the drug is still prohibited for all purposes by the CSA."