Currently, 18 states and the District of Columbia have medical marijuana laws, and more states are about to jump on the bandwagon.
Illinois and New Hampshire may very well become the 19 th and 20 th states, respectively, to adopt medical marijuana laws within the next month or two, says Mason Tvert, communications director for the Marijuana Policy Project .
Colorado and Washington have medical marijuana laws in place and have legalized marijuana for recreational use.
As more states legalize medical or recreational marijuana, the laws and legal issues become more intricate.
And though states may legalize marijuana, the Fed still defines it as an illegal drug.
Federal vs. state law
There's no such thing as "medical" marijuana under federal law, regardless of state laws.
In fact, the Fed still considers marijuana a Schedule I controlled substance under the Controlled Substances Act (CSA) .
So how are states getting by with legalizing medical marijuana?
"It's really up to the Department of Justice, and they have not yet given a formal answer on how they plan on moving forward with all of this," says Tvert.
The DOJ has continually said that they are reviewing the initiatives and watching to see what happens with the legislative process and the establishment of these regulatory systems, he notes.
Back in October 2009, the DOJ issued guidance for federal prosecutors in states with medical marijuana laws.
Dubbed the Ogden Memo , those guidelines explain that "it is likely not an efficient use of federal resources to focus enforcement efforts on individuals with serious illnesses who use marijuana as part of a recommended treatment regimen consistent with applicable state law or their individual non-commercial caregiver."
Yet, those in the business of cultivating, selling or distributing marijuana, along with persons who facilitate those activities knowingly, are violating Federal law and can be prosecuted.
It's important to note that the guidelines did not legalize marijuana.
But other than those guidelines, states are on their own to hash out the details of medical marijuana law.
"Things have been moving along in a somewhat legal gray area when it comes to the interplay between state and federal law," says Tvert.
That could remain the case for a while, or it could be addressed, he says.
State legal issues
There are bound to be questions and concerns when it comes to implementation, regulation and enforcement of marijuana laws at the state level.
"This is the establishment of a new industry," notes Tvert.
For example, Colorado just recently passed a law to limit the amount of THC a person can have in their blood while driving — 5 nanograms of THC per milliliter of blood.
It's a not a per se limit, meaning those charged can argue in court that they weren't really impaired.
But many, including some legislatures, don't agree with the law.
"There just isn't enough evidence to support that law. And there's a very compelling reason to believe that people who are not impaired may be charged with driving while impaired," says Tvert.
Colorado also just passed legislation that requires any publications that have marijuana related advertising to be treated like pornography and kept behind the counter.
Three publications have already filed a suit to block that provision.
In terms of medical marijuana, states must also deal with regulation of dispensaries, transportation of the drug and what constitutes a doctor/patient relationship.
The amount of cannabis a patient can possess is another gray area among many.
For instance, under Michigan law , a patient can legally possess up to 2.5 ounces of marijuana, unless it is medically necessary for the patient to have more.
Will the Fed legalize marijuana?
In December 2012, President Obama said in an interview with Barbara Walters that recreational users of marijuana should not be a "top priority" of federal law enforcement agents in states that have legalized.
"We've got bigger fish to fry," Obama said of pot users in Colorado and Washington during an interview with ABC News' Barbara Walters.
That stance is really nothing new, notes Tvert.
However, Obama also said that Congress needs to have a conversation about reconciling state and federal marijuana laws, which is important.
And there are bills in Congress that address that reconciliation.
One bill, says Tvert, would regulate marijuana like alcohol at the federal level , taking marijuana out of the jurisdiction of the DEA and giving it to the ATF.
Another proposal would immunize people, who are following state and local law, from federal prosecution.
And then there's a proposal to establish a federal marijuana commission , which would address the conflict between federal and state marijuana laws.
There are various ideas about how things are going to move forward, and we don't really know where things stand quite yet, says Tvert.