Under the law in 48 states, here's what can happen when an adult is thought to possess marijuana: Men with guns can go to his home, kick down his door, force him to lay face down on the floor, restrain him with handcuffs, drive him to a police station, and lock him in a cage. If he is then convicted of possessing marijuana, a judge can order that he be locked in a different cage, perhaps for years.
There are times when locking human beings in cages is morally defensible. If, for example, a person commits murder, rape, or assault, transgressing against the rights of others, then forcibly removing him from society is the most just course of action. In contrast, it is immoral to lock people in cages for possessing or ingesting a plant that is smoked by millions every year with no significant harm done, especially when the vast majority of any harm actually done is borne by the smoker.
That there are racial disparities in who is sent to prison on marijuana charges is an added injustice that deserves attention. But if blacks and whites were sent to prison on marijuana charges in equal proportion, jail for marijuana would still be immoral.
America has used marijuana charges to cage people for so long that it seems unremarkable. The time has come to see the status quo for what it is. A draconian punishment for a victimless crime has been institutionalized and normalized, so much so that even proponents of the policy are blind to its consequences. Commentators are criticizing marijuana policy in Washington and Colorado, where the drug was recently legalized. These commentators aren't willing to put their names on an article stating that human beings who possess or smoke marijuana should be locked in cages among child molesters, gang members, and muggers. Yet they reserve their criticism for states that don't do that.