Several cautioned that the issue had raised complex legal and policy considerations — including enforcement priorities, litigation strategy and the impact of international antidrug treaties — that remain unresolved, and that no decision was imminent.

Several options are discussed in the Times article.

A more aggressive option is for the Justice Department to file lawsuits against the states to prevent them from setting up systems to regulate and tax marijuana, as the initiatives contemplated. If a court agrees that such regulations are pre-empted by federal ones, it will open the door to a broader ruling about whether the regulatory provisions can be “severed” from those eliminating state prohibitions — or whether the entire initiatives must be struck down.

Another potential avenue would be to cut off federal grants to the states unless their legislatures restored antimarijuana laws, said Gregory Katsas, who led the civil division of the Justice Department during the George W. Bush administration.

Marijuana use and possession remains a misdemeanor under federal law. But on an enforcement level, the feds don't care about users, they care about the licensing of distributors and establishment of retail outlets. Those are the provisions of both Washington and Colorado's laws they would like to prevent taking effect.

Also, Washington and Colorado's laws are quite different. (Sensible Washington has an analysis of the Washington law here.) The Washington law does not authorize cultivation of any plants for personal use. Growing even one plant at home remains illegal. Passing even one joint to a friend remains a felony. While possessing one ounce of marijuana is allowed, possessing 1.5 ounces is a felony (possessing more than one ounce but less than 40 grams is a misdemeanor.)

Washington's I-502 maintains the classification of marijuana as a Schedule I controlled substance. It also vests total control in the State Liquor Control Board, which will be empowered with setting limits on how much THC can be in the marijuana being sold at licensed stores.

Colorado's Amendment 64 is different. It provides:

3) Personal use of marijuana. Notwithstanding any other provision of law, the following acts are not unlawful and shall not be an offense under Colorado law or the law of any locality within Colorado or be a basis for seizure or forfeiture of assets under Colorado law for persons twenty-one years of age or older:

(a) possessing, using, displaying, purchasing, or transporting marijuana accessories or one ounce or less of marijuana.

(b) possessing, growing, processing, or transporting no more than six marijuana plants, with three or fewer being mature, flowering plants, and possession of the marijuana produced by the plants on the premises where the plants were grown, provided that the growing takes place in an enclosed, locked space, is not conducted openly or publicly, and is not made available for sale.

© transfer of one ounce or less of marijuana without remuneration to a person who is twenty-one years of age or older. (my emphasis)

(d) consumption of marijuana, provided that nothing in this section shall permit consumption that is conducted openly and publicly or in a manner that endangers others.

Whatever the Justice Department decides to do about the regulatory and tax portions of the laws, one thing is clear. Individuals in Colorado who do nothing more than possess an ounce of marijuana, share it with a friend or grow six plants will not be prosecuted. State law will prevent it, and the feds aren't interested.

The reality is the feds can, but don't, charge people for personal use amounts of marijuana absent aggravating factors, such as: the person has a serious prior criminal history; the activity is gang-related or connected to a crime of violence; the offense occurs on federal property or near a school or other prohibited place; the person is also being charged with more serious criminal activity or is on supervised release, probation or state parole.

The feds can't force the state of Colorado or Washington to prosecute marijuana possession cases and they have refrained from doing so under their own enforcement policy. In my view, even if the Justice Department decides to challenge the laws' regulatory provisions, the personal use and possession provisions are unlikely to be affected. As to Amendment 64, the provisions are severable. If one part is found unconstitutional, the remaining parts stay.

The real issue with respect to Amendment 64 is one of policy: whether the feds prefer marijuana to be accessible through controlled and regulated channels as opposed to the black market. The feds should work with the states to make this happen, rather than sue to block the laws.

Bottom line: Showdown between state and federal authorities over retail outlets and commercial growing in Colorado? Maybe. Showdown over possession of an ounce, passing a joint or growing six plants? Unlikely. Chances a showdown on the commercial/regulatory provisions will defeat the Amendment's provisions on authorized personal activities? In my view: slim.