In the government's response to multiple petitions, one reaching an all time high of 74k signatures they justified the ban on marijuana by citing multiple studies, almost all of which have been disproven.
They also cited "common knowledge" facts that have been circulating around the population.
These "facts" have not only never been proven but some of which have been disproven.
For more information on the studies cited in The White house's response read the Frequently Asked Questions at abovetheignorance.org located at: http://abovetheignorance.org/faq.html
Disclaimer: this petition was NOT created by a member of the above site, above the ignorance is in no way associated with me, nor I, them.