Lets take a look at some of the science that is available on the subject. I do not have a lot of time to write today, so here is a great page from drugwarfacts.com:

Since 1996, twelve states have legalized medical marijuana use: AK, CA, CO, HI, ME, MT, NV, NM, OR, RI, VT, and WA. Eight of the twelve did so through the initiative process. Hawaii's law was enacted by the legislature and signed by the governor in 2000, Vermont's was enacted by the legislature and passed into law without the governor's signature in May 2004, Rhode Island's was passed into law over the governor's veto in January 2006, and New Mexico's legislation was signed into law by Governor Bill Richardson on April 2, 2007.

Source: National Organization for the Reform of Marijuana Laws (NORML), from the web at http://www.norml.org/index.cfm?Group_ID=3391, last accessed Jan. 4, 2006, and the Marijuana Policy Project (MPP), from the web at http://www.mpp.org/RI_number_11.html, last accessed Jan. 4, 2006.

The Institute of Medicine's 1999 report on medical marijuana stated, "The accumulated data indicate a potential therapeutic value for cannabinoid drugs, particularly for symptoms such as pain relief, control of nausea and vomiting, and appetite stimulation."

Source: Janet E. Joy, Stanley J. Watson, Jr., and John A Benson, Jr., "Marijuana and Medicine: Assessing the Science Base," Division of Neuroscience and Behavioral Research, Institute of Medicine (Washington, DC: National Academy Press, 1999).

The Institute of Medicine's 1999 report on medical marijuana examined the question whether the medical use of marijuana would lead to an increase of marijuana use in the general population and concluded that, "At this point there are no convincing data to support this concern. The existing data are consistent with the idea that this would not be a problem if the medical use of marijuana were as closely regulated as other medications with abuse potential." The report also noted that, "this question is beyond the issues normally considered for medical uses of drugs, and should not be a factor in evaluating the therapeutic potential of marijuana or cannabinoids."

Source: Janet E. Joy, Stanley J. Watson, Jr., and John A Benson, Jr., "Marijuana and Medicine: Assessing the Science Base," Division of Neuroscience and Behavioral Research, Institute of Medicine (Washington, DC: National Academy Press, 1999).

In the Institute of Medicine's report on medical marijuana, the researchers examined the physiological risks of using marijuana and cautioned, "Marijuana is not a completely benign substance. It is a powerful drug with a variety of effects. However, except for the harms associated with smoking, the adverse effects of marijuana use are within the range of effects tolerated for other medications."

Source: Janet E. Joy, Stanley J. Watson, Jr., and John A Benson, Jr., "Marijuana and Medicine: Assessing the Science Base," Division of Neuroscience and Behavioral Research, Institute of Medicine (Washington, DC: National Academy Press, 1999).

The Institute of Medicine's 1999 report on medical marijuana examined the question of whether marijuana could diminish patients' immune system - an important question when considering marijuana use by AIDS and cancer patients. The report concluded that, "the short-term immunosuppressive effects are not well established but, if they exist, are not likely great enough to preclude a legitimate medical use."

Source: Janet E. Joy, Stanley J. Watson, Jr., and John A Benson, Jr., "Marijuana and Medicine: Assessing the Science Base," Division of Neuroscience and Behavioral Research, Institute of Medicine (Washington, DC: National Academy Press, 1999).

"Conclusions: Smoked and oral cannabinoids did not seem to be unsafe in people with HIV infection with respect to HIV RNA levels, CD4+ and CD8+ cell counts, or protease inhibitor levels over a 21-day treatment."

Source: Abrams, Donald I., MD, et al., "Short-Term Effects of Cannabinoids in Patients with HIV-1 Infection - A Randomized, Placebo-Controlled Clinical Trial," Annals of Internal Medicine, Aug. 19, 2003, Vol. 139, No. 4 (American College of Physicians), p. 258.

"This study provides evidence that short-term use of cannabinoids, either oral or smoked, does not substantially elevate viral load in individuals with HIV infection who are receiving stable antiretroviral regimens containing nelfinavir or indinavir. Upper confidence bounds for all estimated effects of cannabinoids on HIV RNA level from all analyses were no greater than an increase of 0.23 log10 copies/mL compared with placebo. Because this study was randomized and analyses were controlled for all known potential confounders, it is very unlikely that chance imbalance on any known or unknown covariate masked a harmful effect of cannabinoids. Study participants in all groups may have been expected to benefit from the equivalent of directly observed antiretroviral therapy, as well as decreased stress and, for some, improved nutrition over the 25-day inpatient stay."

Source: Abrams, Donald I., MD, et al., "Short-Term Effects of Cannabinoids in Patients with HIV-1 Infection - A Randomized, Placebo-Controlled Clinical Trial," Annals of Internal Medicine, Aug. 19, 2003, Vol. 139, No. 4 (American College of Physicians), p. 264.

"Nevertheless, when considering all 15 studies (i.e., those that met both strict and more relaxed criteria) we only noted that regular cannabis users performed worse on memory tests, but that the magnitude of the effect was very small. The small magnitude of effect sizes from observations of chronic users of cannabis suggests that cannabis compounds, if found to have therapeutic value, should have a good margin of safety from a neurocognitive standpoint under the more limited conditions of exposure that would likely obtain in a medical setting."

Source: Grant, Igor, et al., "Non-Acute (Residual) Neurocognitive Effects Of Cannabis Use: A Meta-Analytic Study," Journal of the International Neuropsychological Society (Cambridge University Press: July 2003), 9, pp. 687-8.

In spite of the established medical value of marijuana, doctors are presently permitted to prescribe cocaine and morphine - but not marijuana.

Source: The Controlled Substances Act of 1970, 21 U.S.C. §§ 801 et seq.

Organizations that have endorsed medical access to marijuana include: the Institute of Medicine, the American Academy of Family Physicians; American Bar Association; American Public Health Association; American Society of Addiction Medicine; AIDS Action Council; British Medical Association; California Academy of Family Physicians; California Legislative Council for Older Americans; California Medical Association; California Nurses Association; California Pharmacists Association; California Society of Addiction Medicine; California-Pacific Annual Conference of the United Methodist Church; Colorado Nurses Association; Consumer Reports Magazine; Kaiser Permanente; Lymphoma Foundation of America; Multiple Sclerosis California Action Network; National Association of Attorneys General; National Association of People with AIDS; National Nurses Society on Addictions; New Mexico Nurses Association; New York State Nurses Association; New England Journal of Medicine; and Virginia Nurses Association.
A few of the editorial boards that have endorsed medical access to marijuana include: Boston Globe; Chicago Tribune; Miami Herald; New York Times; Orange County Register; and USA Today.
Many organizations have favorable positions (e.g., unimpeded research) on medical marijuana. These groups include: The Institute of Medicine, The American Cancer Society; American Medical Association; Australian Commonwealth Department of Human Services and Health; California Medical Association; Federation of American Scientists; Florida Medical Association; and the National Academy of Sciences.
The Controlled Substances Act of 1970 established five categories, or "schedules," into which all illicit and prescription drugs were placed. Marijuana was placed in Schedule I, which defines the substance as having a high potential for abuse, no currently accepted medical use in the United States, and a lack of accepted safety for use under medical supervision. To contrast, over 90 published reports and studies have shown marijuana has medical efficacy.

Source: The Controlled Substances Act of 1970, 21 U.S.C. §§ 801 et seq.; Common Sense for Drug Policy, Compendium of Reports, Research and Articles Demonstrating the Effectiveness of Medical Marijuana, Vol. I & Vol. II (Falls Church, VA: Common Sense for Drug Policy, March 1997).

The U.S. Penal Code states that any person can be imprisoned for up to one year for possession of one marijuana cigarette and imprisoned for up to five years for growing a single marijuana plant.

Source: The Controlled Substances Act of 1970, 21 U.S.C. §§ 801 et seq.

On September 6, 1988, the Drug Enforcement Administration's Chief Administrative Law Judge, Francis L. Young, ruled:

"Marijuana, in its natural form, is one of the safest therapeutically active substances known....[T]he provisions of the [Controlled Substances] Act permit and require the transfer of marijuana from Schedule I to Schedule II. It would be unreasonable, arbitrary and capricious for the DEA to continue to stand between those sufferers and the benefits of this substance."

Source: US Department of Justice, Drug Enforcement Agency, "In the Matter of Marijuana Rescheduling Petition," [Docket #86-22] (September 6, 1988), p. 57.

The DEA's Administrative Law Judge, Francis Young concluded: "In strict medical terms marijuana is far safer than many foods we commonly consume. For example, eating 10 raw potatoes can result in a toxic response. By comparison, it is physically impossible to eat enough marijuana to induce death. Marijuana in its natural form is one of the safest therapeutically active substances known to man. By any measure of rational analysis marijuana can be safely used within the supervised routine of medical care."

Source: US Department of Justice, Drug Enforcement Agency, "In the Matter of Marijuana Rescheduling Petition," [Docket #86-22], (September 6, 1988), p. 57.

Between 1978 and 1997, 35 states and the District of Columbia passed legislation recognizing marijuana's medicinal value.

States include: AL, AZ, AR, CA, CO, CT, FL, GA, IL, IA, LA, MA, ME, MI, MN, MO, MT, NV, NH, NJ, NM, NY, NC, OH, OK, OR, RI, SC, TN, TX, VT, VA, WA, WV, and WI.

And people wonder how we here in California could be confused when there is so much real science backing up our voters' wishes. I encourage all to look more deeply into the real science behind cannabis as a medicine and make informed decisions about what is best for the health and happiness of our society.