We really shouldn't have to ask why marijuana should be legal; the burden is on the government to show why it shouldn't, and none of the explanations for marijuana prohibition are especially convincing. But as long as we have to deal with the reality of marijuana laws, we can present a strong case for repeal.
1. The government has no right to enforce marijuana laws.
There are always reasons why laws exist. While some advocates for the status quo claim that marijuana laws prevent people from harming themselves, the most common rationale is that they prevent people from harming themselves and from causing harm to the larger culture. But laws against self-harm always stand on shaky ground—predicated, as they are, on the idea that the government knows what's good for you better than you do—and no good ever comes from making governments the guardians of culture.
2. Enforcement of marijuana laws is racially discriminatory.
The burden of proof for marijuana-prohibition advocates would be high enough if marijuana laws were enforced in a racially neutral manner, but—this should come as no surprise to anyone familiar with our country's long history of racial profiling—they are most definitely not.
3. Enforcement of marijuana laws is prohibitively expensive.
Six years ago, Milton Friedman and a group of over 500 economists advocated for marijuana legalization on the basis that prohibition directly costs more than $7.7 billion per year.
4. Enforcement of marijuana laws is unnecessarily cruel.You don't have to look very hard to find examples of lives needlessly destroyed by marijuana prohibition laws. The government arrests over 700,000 Americans, more than the population of Wyoming, for marijuana possession every year. These new "convicts" are driven from their jobs and families, and pushed into a prison system that turns first-time offenders into hardened criminals.
5. Marijuana laws impede legitimate criminal justice goals.Just as alcohol prohibition essentially created the American Mafia, marijuana prohibition has created an underground economy where crimes unrelated to marijuana, but connected to people who sell and use it, go unreported. End result: real crimes become harder to solve.
6. Marijuana laws cannot be consistently enforced.Every year, an estimated 2.4 million people use marijuana for the first time. Most will never be arrested for it; a small percentage, usually low-income people of color, arbitrarily will. If the objective of marijuana prohibition laws is to actually prevent marijuana use rather than driving it underground, then the policy is, despite its astronomical cost, an utter failure from a pure law enforcement point of view.
7. Taxing marijuana can be profitable.
A recent Fraser Institute study found that legalizing and taxing marijuana could produce considerable revenue.