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Source: Flickr user Manuel M.V.

It's pretty hard to top the Affordable Care Act, known better as Obamacare, when it comes to controversial topics, but the debate over whether or not marijuana should be a legal drug continues to stir the pot more so than just about any other topic.

Arguing against the momentum embracing the legal marijuana movement over the past decade would be very difficult. Including a few states which have approved but not fully implemented medical marijuana legislation, 23 states and Washington D.C. have approved medical marijuana on a state level to treat select ailments. Furthermore, two states, Washington and Colorado, have approved the legalization of marijuana on a recreational level (though some restrictions still apply) with a handful of other states slated to put marijuana legalization on their ballot in upcoming elections.

However, marijuana's momentum could be about to go up in smoke if a recent survey conducted by the Public Religion Research Institute has any merit.

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Source: Flickr user Brett Levin.

THC-ya later?
According to the PRRI, which released the findings of its 4,500-person study this past week, support for the legalization of marijuana shrank from 51% in 2013 to just 44% in 2014, while opposition to legalization jumped to 50% from 44% in the previous year. As PRRI pointed out in its study, the shift appears to be most apparent in those who either slightly favored legalization in 2013 or those who modestly opposed marijuana legalization, with these on-the-fence respondents appear to have soured on the idea of legalizing marijuana.

It is worth mentioning that PRRI's study comes out on the opposite end of the spectrum of a Gallup poll conducted in October 2013 which demonstrated that, for the first time in history, more respondents favored legalization (58%) than opposed it (39%). But, accounting for this discrepancy is pretty easy considering that respondents in marijuana surveys tend to be highly sensitive to the way a question is worded; and the way the questions were posed to survey participants weren't similar enough between Gallup and PRRI's survey to make a comparison worthwhile.

Mounting obstacles
Regardless of how the public opinion of legal marijuana has vacillated over the recent years, the fact remains that the U.S. Drug Enforcement Agency continues to view marijuana as a schedule 1 drug, meaning that it's illicit on a federal level.

At the moment the federal government has taken a very hands-off approach to regulating marijuana on a state level. In other words, it's chosen to let states like Washington and Colorado regulate marijuana sales within their states, while also allowing the 23 approved medical marijuana states to allow prescriptions to be written by physicians without taking action. However, having the drug approved for use in some states and not others could make for something of a logistical nightmare with regard to ensuring that marijuana sales and distribution remains within a currently "legal" state. If this fails to happen, it's always possible that the federal government could intervene and squash what momentum the industry currently has.

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Source: GW Pharmaceuticals.

Another possible obstacle related to the medical usage of marijuana is whether or not the U.S. Food and Drug Administration will be receptive to approving medicines which are based on cannabinoids found in cannabis plants. The FDA is already hypercritical of approving opioid-based pain therapies due to fears of addiction, so imagine how difficult it could be for pharmaceutical companies like GW Pharmaceuticals (NASDAQ:GWPH), which is currently testing Sativex in three late-stage trials as a potential treatment for cancer pain, to get its drug approved in the U.S.

On one hand GW Pharmaceuticals' research has been quite intriguing. It's discovered five dozen cannabinoids to date and established that humans have natural cannabinoid receptor systems in our body. In short, GW Pharmaceuticals has possibly discovered a way to effect biologic change using derivative aspects of cannabis plants.

But, we have to wonder as consumers and investors whether or not the FDA would be willing to approve a drug derived from the cannabis plant, and, even if approved, if physicians would prescribe it.

A mixed safety picture
Finally, there have been mixed reports emerging on the long-term effects of marijuana usage.

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Source: Flickr user Chuck Coker.

Medical marijuana supporters can point to a recent abstract published by JAMA Internal Medicine which showed that between 1999 and 2010 states that had legalized medical marijuana saw their opioid overdose mortality rate drop by 24.8%. As the study also pointed out, the trend toward lower opioid-related deaths actually improved as time passed following the passage of the law on a state level.

Perhaps the most intriguing find from this study was that utilizing marijuana instead of opioids could actually lead to lower long term health costs. Dealing with fewer overdoses could be beneficial not only for chronic pain sufferers and their wallets, but also for the healthcare system as whole.

Yet, earlier this month a separate study released by the National Drug and Alcohol Research Centre in Australia had markedly different findings. After studying 3,765 adolescents up until age 30, those who were daily marijuana users under the age of 17 were 60% less likely to finish high school or get a college degree, were seven times more likely to attempt suicide, were eight times more likely to try other illicit drugs at some point later in life, and were 18 times more likely to become addicted to marijuana. Understandably there are holes in this study, such as how adults, not adolescents, would have responded to regular marijuana use over time, but it's an indication that long term safety concerns do exist with marijuana use. 

A long road
Despite its many challenges, marijuana's use in the medical community has come a long way, and for that reason alone I'd opine that it can't be written off completely as a potential investment opportunity. On the other hand, I suspect we're still a long ways away from seeing marijuana have a meaningful and/or widespread role in improving patient quality of care. Until a number of the aforementioned concerns are put to rest, I'm afraid emotions rather than facts are going to guide publicly traded marijuana stocks, which may be a dangerous scenario for investors.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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