Investors of all varieties are starting to look at marijuana as less of a stoner's fad and more of a serious business venture.
In some states, drivers are not allowed to have any detectable amount of marijuana in their systems. Other states have set specific numerical standards to establish when a driver is legally impaired by marijuana.
The culture around cannabis is changing, and that influences the way people think about the drug.
Marijuana can require massive amounts of water, and growers have often left behind toxic chemicals, trash and scars on the land. Growing indoors can use excessive amounts of energy, which costs large sums of money and eats up resources.
An analysis by News21 shows that $1.1 billion of the $1.4 billion that the National Institute of Health spent on marijuana research from 2008 to 2014 went toward research on marijuana abuse and addiction. Only $297 million was spent on its effects on the brain and potential medical benefits for those suffering from conditions like chronic pain.
A News21 analysis found that seven of the 23 states that have legalized medical marijuana have mandated laboratory testing, and of those, most are still working to improve their programs.