Greetings from Venezuela
Sorry my english are not good but I will give my opinion.

There are two reasons to reject the criminalization of drugs. The first is ethical and has to do with defining the role of the State in society. Human beings live in society and we create the State to execute certain activities of common interest. But the State should not be involved in issues that strictly concern the individual: among these issues is the consumption preferences of each person.

If I admit that the State has a guardianship to tell me that I can not use cocaine, arguing that it is harmful to my health, then I also have to admit that the State has guardianship to tell me how much salt, refined sugar or red meat I should consume; has guardianship to prohibit cigarettes, beer or motorsports; and if we take the argument to its logical consequence, I must admit that it has guardianship to decide on the education of my son and force him to learn Chinese or Mandarin, when I as a father would prefer that he learn English or French.

There is another reason, which is practical. The fight against drugs has not only been disastrous, but also counterproductive. Today more people die in Mexico because of the violence that the fight against drugs generates, of those who would die for the consumption itself if the drug were legal. If the drugs were legal, the Colombian terrorist group FARC would not have the monopoly that gives it sustenance. If the illegalization of the drug is aimed at less people dying, then the remedy has been worse than the disease.

The fight against drugs has allowed the birth of mafias and cartels that infect society and the State, permeate all institutions and exacerbate corruption; It has encouraged the trafficking of arms that sooner or later end up in the hands of local bandits and kill innocent people who have nothing to do with trafficking or the consumption of narcotics.

If all the violence, death and corruption that the fight against drugs generates had as a reward for their effective disappearance, then those who defend the penalty would have an argument in favor, but the reality is that it is possible to find drugs in any country in the world.