Few people disagree that marijuana is not a good thing. It is a drug, it is addictive, and it damages the body over time. However, there are many factors to consider when making laws about something like smoking marijuana.
Negative Rights. Negative Rights, or the "right to be left alone as long as your actions do not trespass on someone else’s freedoms", would say that a person who does marijuana on their own property, without directly affecting anyone else, has a right to do so. Technically, people who want to smoke marijuana in this way could say that they have a right to do so.
Effectiveness of Laws. Laws against marijuana use appear to be ineffective, comparable with the Prohibition laws of the early 1900’s. In recent studies, as many as one in three say that they have done marijuana at least once. It would be interesting to find exactly how much money is being spent on law enforcement to reach such little success.
Fairness of Laws. Marijuana could very easily be shown to be a less damaging drug than alcohol. How many people do you hear of getting killed by “high” drivers? How much domestic abuse can be attributed to the use of marijuana? Even though alcohol is socially accepted, since the failure of the Prohibition, the facts show that it is a worse drug than weed, and yet alcohol is legal and marijuana is not.
The Purpose of Laws. Few people ever discuss this, but whether or not a law should be created largely depends on the purpose of law in the first place. Law exists to represent the average beliefs of the majority of the people. Benjamin Franklin said it best, “Laws too strict are seldom heeded, laws too lax (or lenient), seldom obeyed.” This is the reason the Prohibition failed. The truth is, there are not enough people who feel that smoking marijuana is a crime worthy of harsh punishment, and more than enough people who are willing to take a chance at a lesser punishment to enjoy the effects of the drug.
For these reasons only, it is neither just, nor fair, nor effective to keep marijuana illegal. A far more productive outcome could be gained by legalizing marijuana, taxing it, and then taking the spending which was previously spent on law enforcement and the revenues from taxing it, and using that money to educate people of the negative effects of the drug.