The following is taken from a dissenting opinion of a District of Columbia appellate judge, joined in by three other judges, in a 1973 case, Moore v. U.S., on whether a non-trafficking addict possessor is subject to criminal punishment. It includes a wealth of sources. At the outset, the judge writes:

In my judgment stigmatization of such persons [addicts] as criminals, rather than treatment of them for their disease, raises serious questions of constitutionality, is contrary to established common law notions of criminal responsibility, and is not mandated by Congress' intent in adopting the relevant legislation.

Moreover, this insensitive approach to drug addiction is tragically counter-productive. Twenty years of rigid criminal enforcement of drug laws against addicts has brought this country, not only a dramatic increase in organized crime, but a harvest of street crime unknown in our history.

The opinion then provides an exhaustive history of opium and heroin.

Opium was used enthusiastically by the medical profession in the American colonies throughout the 18th century....Then, in the first decade of the 19th century, the curiosity of William Serturner, a German chemist, brought about the separation and recognition of the first of the opiate alkaloids. Serturner aptly named the agent morphine, after Morpheus, the god of dreams.

...At the same time, the publication of Thomas DeQuincy's Confessions of an English Opium Eater in 1821 had a far-reaching effect in stimulating its readers -- primarily respectable persons of the American upper class -- to experiment with opiates. Most of DeQuincy's disciples consumed the drug orally, generally in liquid form known as "Laudanum" (tincture of opium), or sometimes as gum or powder. Although opiate indulgence gradually became more common during this era, it did not yet present a problem of serious proportions.

Then came the Civil War:

....the Civil War, with its wholesale carnage and poor medical facilities on the field of battle, caused the first large-scale morphine addiction problem in the United States. The Army's reliance on morphine as a pain-killer became so widespread that morphine addiction during this period came to be known as the "Soldier's Disease." Indeed, one of the more unfortunate consequences of the war was the creation of a large class of ex-soldier addicts, and estimates of addiction in the postwar years ran as high as four per cent of the population.

In 1898, heroin, also an alkaloid derivative of opium, was invented by another German Scientist. As I've written before, heroin was originally thought to be a "hero drug" that would cure Civil War soldiers and others of morphine addiction. From the Moore dissent:

...in 1898 when Dresser, a German scientist, devised a method to modify morphine into a new alkaloid derivative of opium -- diacetylmorphine, commonly referred to as heroin. Initially, the basic characteristics of this new drug were completely misunderstood. Since heroin appeared to relieve the symptoms of morphine withdrawal, it was hailed as a cure for morphine addiction, and heroin was rapidly substituted for morphine in cough medicines and tonics. Many writers extolled the pain-killing qualities of the drug while assuring readers that it was free of addiction liability. The naive myth that heroin could cure morphine addiction exploded soon after 1900, when it was finally realized that heroin itself possessed an even greater addiction potential than morphine. But despite the urgent, if somewhat belated,warnings of the medical profession, heroin had gained a foothold and was here to stay.

Perhaps the most unfortunate chapter in the early history of American drug abuse involved the vicious practices of the patent medicine business of the late 19th and early 20th centuries. These general curatives, which often contained a potent concentration of some narcotic, were sold without restraint over the counters of pharmacies and were used indiscriminately to treat everything from simple headache to angina pectoris. Through such wonder-working medicants as Mrs. Winslow's Soothing Syrup, Dr. Cole's Catarrh Cure and Perkins' Diarrhea Mixture, opium, morphine, codeine and cocaine were spooned regularly into children as well as adults. And although these potions usually relieved the symptoms for which they were taken, they also caused physical dependence in the user.

As the public grew concerned over their "drug habits," the patent medicine manufacturers readily responded with more nostrums offered as cures for addiction. Yet most of these "cures" were in reality preparations containing a different opiate, so that the user merely substituted one drug for another, with the result that his addiction frequently was intensified.

Then the feds stepped in, going after doctors who were treating addicts under the Harrison Act.

The inevitable followed..... agents of the Bureau of Narcotics launched what has aptly been termed a "reign of terror" against the medical profession's treatment of addiction. Even those doctors who prescribed these drugs in good faith as part of their therapeutic treatment of the disease were subjected to prosecution, and the clinics which had opened so hopefully only a few years before were abruptly shut down.

Within the short span of three years the medical profession was "bullied into submission" and was forced to extricate itself almost entirely from the treatment of addicts.

In 1925, the Supreme Court, in Linder v. United States, a case involving a doctor challenging his conviction for prescribing to an addict, reversed the conviction and ruled that doctors could treat addicts.

[The Act] says nothing of 'addicts' and does not undertake to prescribe methods for their medical treatment. They are diseased and proper subjects for such treatment, and we cannot possibly conclude that a physician acted improperly or unwisely or for other than medical purposes solely because he had dispensed to one of them, in the ordinary course and in good faith, four small tablets of morphine or cocaine for relief of conditions incident to addiction.

Then the feds' propaganda campaign began:

Following Linder, one might reasonably have expected a sudden and enthusiastic resurgence of medical interest in addiction. Unfortunately, such was not the case. Soon after Behrman, a large-scale propaganda campaign was initiated, from which we derive many of our present misconceptions of the addict and his affliction.

Although addicts had traditionally been viewed as victims of an unfortunate illness, this campaign sought, quite successfully, to attach the stigma of criminality to addiction. The addict was portrayed as a moral degenerate, and the myth of the "dope-crazed sex fiend" was perpetrated. Grossly inflated estimates of the number of addicts were circulated, and as the public's alarm over the "dope menace" swept the nation, medical approaches to the problem of addiction fell gradually into disfavor.

...Thus, due largely to the misguided efforts of federal officials, the medical profession for more than half a century now has been forced to abdicate its role in the treatment of addiction. And by depriving addicts of treatment on the one hand, while criminalizing their illness on the other, this nation adopted a policy toward addiction unique in all the world.

...As one scholar has capsuled the situation:

"The present program of handling the drug problem in the United States is, from the legal viewpoint, a remarkable one in that it was not established by legislative enactment or by court interpretation of such enactments. Public opinion and medical opinion had next to nothing to do with it. It is a program which, to all intents and purposes, was established by the decisions of administrative officials of the Treasury Department of the United States.

As a result:

Over the years the consequences of this policy have been disastrous for both the individual addict and society as a whole. With the closing of the narcotics clinics and the sudden elimination of medical assistance in the mid-1920's, thousands of addicts were left stranded without any legitimate source from which to obtain their supplies. "Treatment" was ceded to the underworld, which eagerly accepted the invitation. Within a few years, a multimillion dollar industry had developed, and the price of drugs skyrocketed. For the first time, addicts were compelled to turn to crime as a means of obtaining funds to support their addiction. Gradually, a vast criminal infrastructure was developed to distribute illicit narcotics primarily to the lower socio-economic classes in our cities, and drug addiction became almost exclusively a problem of the urban poor.

After WWII, drug usage increased, prompting Congress to increase penalties for drugs.

The social behavior of the addict depends also upon the legal and social context in which it occurs, and with the realization that criminal behavior is neither a necessary nor even a logical consequence of the disease, we must face the undeniable fact that our criminalization of addiction has, in part, become a self-fulfilling prophecy.

...our existing narcotics problem is largely a reflection of all that has gone before. Yet there is little in the past of which we can be proud, for our policies have branded these unfortunate individuals as the outcasts of society and forced them unnecessarily to lives of crime and degradation.

Substituting treatment for criminal stigmatization, as I suggest, will not eliminate all or even most of the remaining problems, but it does represent one step further toward what hopefully will become an age of enlightenment in our attitudes toward the addict and his disease.

Not every heroin user becomes addicted.

Contrary to popular belief, not all persons who enter this stage will eventually become addicts. Indeed, most experts now agree that even repeated use of heroin will not necessarily or even usually result in addiction unless the user's personality is particularly susceptible to the psychological effects of the drug. Unlike the hallucinogens, heroin does not produce a positive euphoric "high" of intensified sensory input. Rather, the drug has a calming, depressant effect which dulls the general sensibilities and allays feelings of pain, insecurity or discomfort. The heroin "high" is essentially escape-oriented, and a direct correlation exists between the pleasure one derives from the drug and the user's psychic need to avoid reality. Thus, although the psychologically stable individual [may enjoy his experience with heroin, his satisfaction generally is not so great as to draw him irresistibly to excessive use. As a result, many such persons are able to administer heroin on an occasional basis without ever becoming addicted.

At the other end of the spectrum:

The situation is quite different, however, for those users whose psychological makeup renders them particularly prone to addiction. Although the precise nature of the disorders causing addiction proneness may vary, its symptoms are readily identifiable, including such characteristics as an oversensitivity to rejection, an inability to enter into close associations with others, difficulty in sexual role identification, an inability to cope with reality, and a tendency to be overcome by a sense of inadequacy, futility and despair. For the individual exhibiting all or some of these symptoms, the use of heroin may be seen as an attempt at personal adjustment. The drug fulfills a specific function in his psychological economy, and when experiencing its effect he finds that the previously intolerable frustrations and anxieties of his daily existence mysteriously evaporate. Feelings of pain, hunger, inadequacy and fear are extinguished, and he experiences a sense of aloofness and self-sufficiency which he is unable to attain in the real world. Indeed, he "has discovered something he may well have been searching for all his life."

....Thus during the "honeymoon period" of occasional use the addiction prone individual finds the psychic effects of the drug virtually irresistible and, spurred on by a false sense of security generated by the drug itself, he begins gradually to increase the frequency of his doses. Due to the development of tolerance, however, he soon discovers that the same dose fails to produce the original euphoric effect, and he must continually increase the size of his dosage in order to achieve the desired "high." 1Then, after a period of excessive use, physical dependence develops. The user is "hooked" -- he now needs the drug not only to alleviate his underlying psychological instability, but also to avoid the misery of withdrawal.

Withdrawal is quite a miserable experience. I'll spare the details and talk about post-withdrawal:

The acute symptoms of withdrawal generally reach a peak between 48 and 72 hours after the last dose and subside gradually during the following week. Distress may continue for weeks, however, and it may be months before physiological stability is achieved. But as terrifying as the withdrawal experience may seem, it does not end the addiction, for the underlying psychological dependence of the addict remains uncured. As a result, "addiction to heroin and to other opiates, once established, has the characteristics of a chronic relapsing disease."

This psychological dependence, which derives initially from the basic personality disorders of the addict, develops through a process of conditioning. Each time the drug is injected, tension, pain and anxiety are reduced, and the memory of this experience beckons as a panacea for all the frustrations of daily living. Gradually, a complex set of conditioned responses is acquired, which tends to perpetuate continued use. When physical dependence emerges, the need to use the drug to avoid withdrawal further reinforces the addict's psychic reliance, and eventually he requires heroin to relieve all forms of tension, no matter how slight. Indeed, the addict's psychological dependence on the drug is generally considered to be the most powerful aspect of the disease.

Punishment is futile.

Thus with the confluence of these three factors -- physical dependence, psychological dependence and tolerance -- the addict is caught in the spiralling web of his addiction. Unable to face reality without the drug on the one hand, and requiring it to avoid the horrors of withdrawal on the other, he turns repeatedly to the drug to obtain relief. Yet with each additional dose, the withdrawal becomes more intense, the psychological dependence greater, the tolerance increased, and the ability to escape voluntarily less likely.

Eventually, he loses all control, and "struggle as he may, the curious and inexorable process overwhelms him. No outer moral compulsion can stay it; no authoritarian decree can cut it short. Punishment is meaningless, imprisonment futile, in halting the relentless course of the disease.

Addiction is not a pleasurable experience.

....The confirmed addict is in fact a worried, troubled, harried individual. Misery, alienation and despair, rather than pleasure and ecstasy, are the key features of his existence. Since he cannot obtain his supply of drugs legally, his entire life becomes bound up in a ceaseless quest for heroin. He loses all desire for socially productive work, food, sex, companionship, family ties and recreation...

Caveat on work productivity:

Although addiction may cause a loss of vitality which can impair the addict's ability to work productively, most addicts can perform in a work capacity in a relatively normal fashion if the drug is readily available to them.

Caveat on health issues:

Contrary to popular belief, even prolonged heroin use does not cause permanent organic damage. Thus the illnesses most frequently associated with addiction, such as severe tooth decay, malnutrition and hepatitis, are due to the addict's preoccupation with drugs, the impurity of the drugs he purchases on the black market, and his poverty, rather than to addiction itself.

On Overdoses:

Most overdoses are due to the impurity of the drug injected. On the black market, the substance purchased may range in purity from about 1% to 30%....The remainder usually consists of natural impurities and adulterants such as lactose, dextrose, quinine and mannitol. Thus the user never knows what dosage he is actually getting, and he has no protection from the adulterants,
which may sometimes be even more dangerous than the drug itself.

The same holds true today. If heroin deaths are rising, it's more likely not the heroin per se, but the combination of heroin with potent other drugs like Fentanyl, that is most likely responsible. (This is not to say that Hoffman's death resulted from such a combination as the autopsy results have not yet been released and police are saying Fentanyl was not present.) But since heroin can't be gotten legally, the user has no way to know what the seller put in the heroin. Shooting up is a crapshoot.

If heroin use is indeed rising due to it being a cheaper and readily available substitute for pain pills, the answer seems clear: End the war on pain pills. Let people use them. At least they won't die shooting up in a bathroom because the drug they obtained through the black market, in an alley or at their ATM machine, contained a lethal combination of multiple substances.

Oxycontin and pain meds aren't causing heroin deaths. It is the criminalization of pain meds and the doctors who prescribe them , putting them in short supply compared to demand, that is leading users to seek alternatives, which often can be deadly.

On society's responsibility, the dissent writes in the Moore opinion:

Yet the misery of the addict is not his alone, for as members of a common society we all share in the responsibility for the conditions which have helped to make him what he is. Indeed, no matter how low he sinks, he cannot lose his right to justice; and the lower he sinks, the greater is his claim to our concern.

.... the federal narcotics statutes cannot be construed as exposing non-trafficking addict possessors to criminal punishment. Indeed, prosecution and conviction of such persons, appellant argues, would raise serious questions of constitutionality, is contrary to established common law notions of criminal responsibility, and is not mandated by Congress' intent in adopting the relevant legislation....I find these arguments compelling.