Jonathan Caulkins
Carnegie Mellon University, Heinz School, Faculty Member
The United States Drug Enforcement Administration's (DEA's) System to Retrieve Information from Drug Evidence (STRIDE) data contain records of acquisitions of illegal drugs by undercover agents and informants of the DEA and... more
The United States Drug Enforcement Administration's (DEA's) System to Retrieve Information from Drug Evidence (STRIDE) data contain records of acquisitions of illegal drugs by undercover agents and informants of the DEA and Metropolitan Police of the ...
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Changing a substance’s legal status is a perennial policy question that can be answered in many different ways. The focus of this chapter is on cannabis, the drug that has attracted the most attention because of its widespread use and... more
Changing a substance’s legal status is a perennial policy question that can be answered in many different ways. The focus of this chapter is on cannabis, the drug that has attracted the most attention because of its widespread use and relatively favourable risk profile in comparison with several legal substances.
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The use of illicit psychoactive substances is commonplace in many parts of the world, with significant variations in the extent of drug use and problem use. This reflects differences in drug markets, drug availability, and legislation, as... more
The use of illicit psychoactive substances is commonplace in many parts of the world, with significant variations in the extent of drug use and problem use. This reflects differences in drug markets, drug availability, and legislation, as well as political, economic, and social conditions. Cultural and historical conditions can also play an important role. Overwhelming evidence from epidemiological research conducted over the past 50 years shows that adolescence is the period of greatest risk for the initiation of drug use. Most of those who have tried illicit drugs do not go on to develop drug dependence or drug-related problems. Problem drug users are more often males and are likely to have a family history of substance dependence, delinquent behaviour, and mental health problems. Strategies to prevent drug use or drug related harms need to address the complexity of drug-related problems.
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Psychoactive substances have assumed increasing public attention in most parts of the world, especially when they are defined broadly to include alcohol, tobacco, illicit drugs, and certain types of legal pharmaceutical agents that have... more
Psychoactive substances have assumed increasing public attention in most parts of the world, especially when they are defined broadly to include alcohol, tobacco, illicit drugs, and certain types of legal pharmaceutical agents that have high dependence potential. The effects these substances have on individuals and society depend on a variety of factors, including the pharmacological properties of each drug, the way the drugs are ingested, their cultural meanings in everyday life, the reasons for using them, and the harms associated with their misuse. Public discussion of drug policies has too often failed to take these complexities into account. Simplistic views that all drugs are the same and all are equally dangerous not only limit our understanding of drug-related problems but also impair our ability to develop meaningful policy responses. Advances in psychiatry, psychology, neurobiology, cultural anthropology, epidemiology, and a variety of other disciplines have substantially ...
This new edition provides updates about what is happening in the states and countries that have changed their marijuana laws; looks at the results of legalization measures in the United States, including effects on usage, health, safety,... more
This new edition provides updates about what is happening in the states and countries that have changed their marijuana laws; looks at the results of legalization measures in the United States, including effects on usage, health, safety, and revenues; and considers next steps in light of recent legalization measures.
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Drug policy research is the application of policy analysis in the substance abuse domain with a level of rigor that merits publication in academic journals on the grounds that the methods and/or results can provide foundational insights... more
Drug policy research is the application of policy analysis in the substance abuse domain with a level of rigor that merits publication in academic journals on the grounds that the methods and/or results can provide foundational insights upon which subsequent analyses might draw. Policy analysis in turn is an interdisciplinary field that strives to objectively and empirically understand the consequences of different public policy interventions, including both retrospective evaluation of past interventions and prospective projections of contemplated interventions. It is useful to distinguish three types of policy analysis: 1)Analysis of net effects on society as a whole (a "social planner's perspective"), 2)Distributive analysis of effects on each significant group of stakeholders, and 3)Political analysis of what convergence of forces can push through a piece of legislation or other policy change.
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International prohibitions create asymmetries; production and transshipment concentrate in relatively few places that bear the bulk of the negative externalities created by the illegal trade. These externalities fuel calls for altering... more
International prohibitions create asymmetries; production and transshipment concentrate in relatively few places that bear the bulk of the negative externalities created by the illegal trade. These externalities fuel calls for altering the United Nations treaty framework and for individual nations to legalize outside of the framework. Analyses of the pros and cons of legalization usually adopt the perspective of a single nation acting in isolation. However, one nation’s legalization alters incentives for others to act, and not always in obvious ways. So the proper perspective is that of a dynamic game.The primary contribution of this paper is to make the case for analyzing legalization as a strategic game, but it also offers preliminary analysis for the case of cocaine. Tentative conclusions include:
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Markets for drugs, prostitution and other prohibited goods and services are just that … markets. The first duty of economists is to show that the tools of conventional economics are applicable for the illegal markets as well. That is... more
Markets for drugs, prostitution and other prohibited goods and services are just that … markets. The first duty of economists is to show that the tools of conventional economics are applicable for the illegal markets as well. That is easily enough done with respect to demand. Many studies have shown that demand for illicit drugs is downward
Generally more is known about drug use and demand than about markets and supply, in large part because population survey data are available while market data are not. Although the household population represents a relatively small... more
Generally more is known about drug use and demand than about markets and supply, in large part because population survey data are available while market data are not. Although the household population represents a relatively small proportion of users of hard drugs, it represents a large proportion of the population using marijuana and participating in marijuana markets. This paper provides a description of marijuana market and acquisition patterns as reported by participants in the 2001 National Household Survey on Drug Abuse. We find that most respondents obtain marijuana indoors (87%), from a friend or relative (89%), and for free (58%). Retail marijuana distribution appears to be embedded in social networks, rather than being dominated by “professional ” sellers. Despite these contrasts with stereotypical street markets for cocaine and heroin, there are also similarities, such as evidence of quantity discounts and a minority of users accounting for the majority of purchases. We e...
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Although a part of the property crime rate can be explained by predatory crime committed by drug users, research often recommends not to enforce against drug crime, because law enforcement resource allocations accompanying strong drug law... more
Although a part of the property crime rate can be explained by predatory crime committed by drug users, research often recommends not to enforce against drug crime, because law enforcement resource allocations accompanying strong drug law enforcement lead to more property crime. We develop a dynamic model including a drug court program to analyse the impact of drug enforcement on property crime. In this model it is almost always optimal to enforce, but the amount of drug enforcement expenditures and its time path vary depending on the parameter settings. Key parameters are the elasticity of demand of the drug and the estimation of the social costs of drug use. Whether enforcement is done, depends also on the initial value of the number of users. In this model it is optimal not to enforce only for an initial stock of users greater than a certain threshold and very low social costs of drug use or a low absolute value for the short term elasticity of demand.
The present paper introduces several models concerning drug initiation and drug epidemics that extend traditional single and multi-state dynamic models by explicitly considering the age distribution of users. This age-specificity yields... more
The present paper introduces several models concerning drug initiation and drug epidemics that extend traditional single and multi-state dynamic models by explicitly considering the age distribution of users. This age-specificity yields more realistic models, because both human behaviour and the influence of personal relationships can depend on age and the age difference. Furthermore, prevention programmes—especially school-based programmes—can be targeted to reach certain age groups. The models allow the dynamics of drug epidemics to be reproduced in greater detail. The models can be used either for studying the features of drug initiation or for discovering how best to allocate resources to prevention programmes for different age groups.
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Trajectories of drug use are usually studied empirically by following over time persons sampled from either the general population (most often youth and young adults) or from heavy or problematic users (e.g., arrestees or those in... more
Trajectories of drug use are usually studied empirically by following over time persons sampled from either the general population (most often youth and young adults) or from heavy or problematic users (e.g., arrestees or those in treatment). The former, population-based samples, describe early career development, but miss the years of use that generate the greatest social costs. The latter, selected populations, help to summarize the most problematic use, but cannot easily explain how people become problem users nor are they representative of the population as a whole. This paper shows how microsimulation can synthesize both sorts of data within a single analytical framework, while retaining heterogeneous influences that can impact drug use decisions over the life course. The RAND Marijuana Microsimulation Model is constructed for marijuana use, validated, and then used to demonstrate how such models can be used to evaluate alternative policy options aimed at reducing use over the ...
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Generally more is known about drug use and demand than about markets and supply, in large part because population survey data are available while market data are not. Although the household population represents a relatively small... more
Generally more is known about drug use and demand than about markets and supply, in large part because population survey data are available while market data are not. Although the household population represents a relatively small proportion of users of hard drugs, it represents a large proportion of the population using marijuana and participating in marijuana markets. This paper provides a description of marijuana market and acquisition patterns as reported by participants in the 2001 National Household Survey on Drug Abuse. We find that most respondents obtain marijuana indoors (87%), from a friend or relative (89%), and for free (58%). Retail marijuana distribution appears to be embedded in social networks rather than being dominated by “professional” sellers. Despite these contrasts with stereotypical street markets for cocaine and heroin, there are also similarities, such as evidence of quantity discounts and a minority of users accounting for the majority of purchases. We est...
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Software engineers and businesses must make the difficult decision of how much of their budget to spend on software security mitigation for the applications and networks on which they depend. In this article, we introduce a novel method... more
Software engineers and businesses must make the difficult decision of how much of their budget to spend on software security mitigation for the applications and networks on which they depend. In this article, we introduce a novel method of optimizing, using Integer Programming (IP), the combination of security countermeasures to be implemented in order to maximize system security under fixed resources. We describe the steps involved in our approach, and discuss recent results with a case study client. Introduction Software engineers and their customers are continuously faced with a complex and frustrating decision: Given a fixed budget, which combination of vulnerability mitigation actions produces optimal security for a system? In a world with no budgetary or temporal constraints, one could invest in whatever tools or training deemed necessary to safeguard the applications and networks on which customers depend. Engineers could spend arbitrary amounts of time and money patching exi...
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In this paper we set up a model of interacting drug epidemics by taking the ”direct-product” of variations on a one-dimensional optimal control model that exhibits a so-called DNSS or Skiba threshold. Such a threshold reflects in drug... more
In this paper we set up a model of interacting drug epidemics by taking the ”direct-product” of variations on a one-dimensional optimal control model that exhibits a so-called DNSS or Skiba threshold. Such a threshold reflects in drug policy the well-established paradigm of ”eradication vs. accommodation”; that is, depending on the initial state, stabilizing a drug market at either a low or a high level of use is optimal. We investigate whether and how this ”eradication vs. accommodation” paradigm extends to higher dimensional models and whether and how the presence of a second drug can alter the optimal policy description for the first drug. The main results are, first, the presence of a second drug market can dramatically alter or even reverse the optimal policy prescription for the first drug market. Second, with interacting drug markets ”eradication vs. accommodation” is no longer a binary choice. Rather, we observe a fascinating series of situations with multiple optimal steady...
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This paper explores the idea that drug markets may be chaotic in a mathematical sense by considering a discrete-time model of populations of drug users and drug sellers for which initiation into either population is a function of relative... more
This paper explores the idea that drug markets may be chaotic in a mathematical sense by considering a discrete-time model of populations of drug users and drug sellers for which initiation into either population is a function of relative numbers of both populations. The structure of the system follows that considered in an arms control context by Behrens, Feichtinger and Prskawetz (Behrens D.A., Feichtinger G., & Prskawetz A. (1997). Complex Dynamics and Control of Arms Race. European Journal of Operations Research, 100, 192-215). The model presented in this paper summarizes prerequisites for possible chaotic behavior of the number of addicts and drug dealers frequenting a local drug market. Interestingly, even if the uncontrolled market dynamics do not exhibit chaotic patterns, a static intervention like removing a constant fraction of addicts each time period can easily create chaos--but even if static control would create chaos, dynamic controls can be crafted that avoid it. Esp...
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Since drug use and related problems substantially change over time, it seem plausible that drug interventions should vary too. Static interventions applied to a dynamic process may be counter-productive. Therefore we formulate the choice... more
Since drug use and related problems substantially change over time, it seem plausible that drug interventions should vary too. Static interventions applied to a dynamic process may be counter-productive. Therefore we formulate the choice between treatment and prevention spending in the framework of dynamic optimal control. Prevention is the most appropriate control policy when there are relatively few heavy users, i.e. in the beginning of an epidemic. Treatment, however, is most sufficient to support the decline of drug abuse optimally. Additionally these models are able to generate a number of interesting insights, among which are (1) costs of interventions as well as social cost associated with the quantity consumed increase with the delays in the starting year of control, (2) people who perceive drug use to be costly for society should favor greater drug control spending per gram consumed and allocate a grater proportion of that spending to prevention. + This research was partly ...
BACKGROUND Cannabis legalization and the arrival of nonmedical fentanyl are fundamentally altering North American drug markets. An essential part of that change is the ability to produce large quantities of these drugs at low costs, which... more
BACKGROUND Cannabis legalization and the arrival of nonmedical fentanyl are fundamentally altering North American drug markets. An essential part of that change is the ability to produce large quantities of these drugs at low costs, which is like a technological breakthrough in their production technology. This essay explores possible future consequences of these trends. METHODS Descriptive statistics, historical analogy and economic reasoning. RESULTS In North America, wholesale prices for cannabis and opioids - in the form of illegally manufactured fentanyl and other new synthetic opioids - are radically lower than they were a decade ago. Retail prices for cannabis have fallen commensurately, but not yet for opioids. Historical analogies suggest that very large declines in price can have effects on use that go beyond just an expansion of traditional patterns of consumption. CONCLUSION For cannabis and opioids in North America, conditions are ripe for significant changes in not onl...
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The COVID-19 pandemic is causing economic and social change. Moderated by David Banks, the Director of the Statistical and Applied Mathematical Sciences Institute (SAMSI), six eminent scientists who study different aspects of social... more
The COVID-19 pandemic is causing economic and social change. Moderated by David Banks, the Director of the Statistical and Applied Mathematical Sciences Institute (SAMSI), six eminent scientists who study different aspects of social change and public policy came together to discuss the impacts of the COVID-19 pandemic on the U.S. and the world. The discussion took a range of quantitative perspectives on how to respond to the crisis and to forecast what challenges lie ahead. Specific topics include the role of data science, strategies for beginning to reopen the economy, the international impact of the disease, and its effect upon universities.
Most nations have responded to the COVID-19 pandemic by locking down parts of their economies starting in early 2020 to reduce the infectious spread. The optimal timing of the beginning and end of the lockdown, together with its... more
Most nations have responded to the COVID-19 pandemic by locking down parts of their economies starting in early 2020 to reduce the infectious spread. The optimal timing of the beginning and end of the lockdown, together with its intensity, is determined by the tradeoff between economic losses and improved health outcomes. These choices can be modelled within the framework of an optimal control model that recognises the nonlinear dynamics of epidemic spread and the increased risks when infection rates surge beyond the healthcare system’s capacity. Past work has shown that within such a framework very different strategies may be optimal ranging from short to long and even multiple lockdowns, and small changes in the valuation on preventing a premature death may lead to quite different strategies becoming optimal. There even exist parameter constellations for which two or more very different strategies can be optimal. Here we revisit those crucial questions with revised parameters refl...
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Nations struggled to decide when and how to end COVID-19 inspired lockdowns, with sharply divergent views between those arguing for a resumption of economic activity and those arguing for continuing the lockdown in some form. We examine... more
Nations struggled to decide when and how to end COVID-19 inspired lockdowns, with sharply divergent views between those arguing for a resumption of economic activity and those arguing for continuing the lockdown in some form. We examine the choice between continuing or ending a full lockdown within a simple optimal control model that encompasses both health and economic outcomes, and pays particular attention to when need for care exceeds hospital capacity. The model shows that very different strategies can perform similarly well and even both be optimal for the same relative valuation on work and life because of the presence of a so-called Skiba threshold. Qualitatively the alternate strategies correspond to trying essentially to eradicate the virus or merely to flatten the curve so fewer people urgently need healthcare when hospitals are already filled to capacity.
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Among the 47 options reviewed in this book, most show some evidence of effectiveness in at least one country, but the evidence is less than definitive for many others, either because the interventions are ineffective, or the research is... more
Among the 47 options reviewed in this book, most show some evidence of effectiveness in at least one country, but the evidence is less than definitive for many others, either because the interventions are ineffective, or the research is inadequate. Unfortunately, policies that have shown little or no evidence of effectiveness continue to be the preferred options of many countries and international organizations. The evidence reviewed in this book supports two overarching conclusions. First, an integrated and balanced approach to evidence-informed drug policy is more likely to benefit the public good than uncoordinated efforts to reduce drug supply and demand. Second, by shifting the emphasis toward a public health approach, it may be possible to reduce the extent of illicit drug use, prevent the escalation of new epidemics, and avoid the unintended consequences arising from the marginalization of drug users through severe criminal penalties.
Policies affecting the type, amount, and organization of health and social services play an important role in the overall effectiveness of a service system. Countries differ markedly in their service systems, which vary in terms of the... more
Policies affecting the type, amount, and organization of health and social services play an important role in the overall effectiveness of a service system. Countries differ markedly in their service systems, which vary in terms of the availability, accessibility, coordination, cost-effectiveness, and coerciveness of treatment and harm-reduction services. There are now a large number of evidence-informed health and social services that are ready for implementation in systems of care in both low and high-income countries. These interventions, along with innovations in the organization of service systems, can directly address access, equity, and coordination. Coordination between the criminal justice system, mental health services, primary health care, and the treatment system can reduce drug use, improve health, prevent crime, and decrease recidivism. Health and social services organized within an integrated system, can have an impact on the population in a variety of areas targeted ...
Illegal drugs are commodities that are bought and sold in markets. Many farmers are engaged in small amounts of drug growing in the producing countries, but there are comparatively small numbers of refiners, smugglers, and top-level... more
Illegal drugs are commodities that are bought and sold in markets. Many farmers are engaged in small amounts of drug growing in the producing countries, but there are comparatively small numbers of refiners, smugglers, and top-level importers. Compared to most legal markets, there are many sellers relative to the number of buyers in drug markets. One consequence of the network character of drug distribution is its resilience. Eliminating individual players or even entire organizations within a mature drug distribution network has little impact on the ability of the network as a whole to transport drugs from their source to the customers. This adaptability of mature drug distribution networks limits the ability of enforcement authorities to eradicate mass-market drugs.