I disagree with your perceived loss of justice should drug use be legalized. Laws exist to protect people. Drug laws have only served to hurt nearly every person on earth when considering supply chain and tangential effects. By opening up the law to allow people to self medicate we are actually reducing harm at every step from the companies producing raw materials to the end users. To only consider a solution that outlaws the existence of an addict is inhumane, immoral, impossible, and outright delusional. To learn more about these topics and hopefully gain some empathy for addicts I suggest reading Gabor Matès "In the realm of hungry ghosts."
https://barnesandnoble.com/w/in-the-realm-of-hungry-ghosts-g...