Mark Kleiman


Over the past two decades, opinion about cannabis has shifted sharply. In 1995, legalization was more or less a fringe opinion, with the support of less than a quarter of the public. Now it commands a slim but growing majority. The topic remains fiercely controversial, with legalization advocates gleefully promising a wealth of good results and drug warriors dourly predicting disaster.

This page will be home to a variety of views on the topic, including views not shared by its organizers. But since we’re doing the selection, readers have a right to know our opinions. They are as complex as the topic, and not all of us agree. But the three central points are these:

  1. Legalization, if it happens – as now seems likely – will have both good and bad effects. It will eliminate the evils of prohibition – illicit markets and enforcement against them, arrests, incarceration, product of unreliable quality – but, in all probability, increase the number of people suffering from cannabis-related substance use disorder, and especially the number of early teenagers using enough to damage their life-prospects.
  2. The results of legalization are unpredictable; full legal production and sale of cannabis has not been the policy anywhere in the developed world since the Single Convention was adopted in the early 1960s. History, biology, and economics can help us separate more likely outcomes from less likely ones, but anyone who makes confident predictions is either fooling himself or trying to fool others.
  3. The extent, both of the good results and the bad ones, depends on details of policy, and especially policies having to do with prices and with information.  Wiser policies can lead to better outcomes. Our chances of finding such policies will be slimmer if advocates continue to insist that legalization will have only good results and opponents continue to insist that it will have only bad ones, and to debate the question whether to legalize without any consideration of the problem of how to legalize.
  4. We have much to learn from the experience of medical marijuana and from the commercial legalization now underway in Colorado and Washington.  Treating every new result and finding as simply a weapon in the battle over legalization – trumpeting it if it happens to fit your preconceived view, denying its relevance if it comes out unfavorably – presents a barrier to learning those lessons.

It’s not easy to approach a passionately-debated question in a scientific spirit. But that’s what we’re trying to do here.


Mark A.R. Kleiman, MPP, Ph.D., is the chairman of BOTEC Analysis Corporation and a world-renowned expert in crime reduction, justice, and drug policy. In addition to his work with BOTEC, Dr. Kleiman is a Professor of Public Policy and the Director of the Crime Reduction & Justice Initiative at New York University’s the Marron Institute, co-editor of the Journal of Drug Policy Analysis, the organizer of the group blog called The Reality-Based Community and a member of the Committee on Law and Justice of the National Research Council. 

BOTEC Analysis Corporation was the lead contractor in implementing a legal cannabis market in Washington State and is currently advising Jamaica's Ministry of Industry, Investment and Commerce on the development of regulations to guide Jamaica's nascent medical marijuana and industrial hemp sectors.  

Mark taught at Harvard and the University of Rochester before joining the faculty at UCLA in 1995. In July of 2015, he moved to New York University where he is a Professor of Public Policy at the Marron Institute of Urban Management.  He is also an adjunct scholar at the Center for American Progress and a member of the board of Drug Strategies. He has served as a visiting professor at Harvard Law School and as the first Thomas C. Schelling Distinguished Visiting Professor at the School of Public Policy at the University of Maryland. 

Outside of academia, he has worked for the U.S. Department of Justice (as Director of Policy and Management Analysis for the Criminal Division), for the City of Boston (as Deputy Director for Management of the Mayor's Office of Management and Budget), for Polaroid Corporation (as Special Assistant to the CEO, Edwin Land), and on Capitol Hill (as a legislative assistant to Congressman Les Aspin)

His books include When Brute Force Fails: How to Have Less Crime and Less Punishment (named by The Economist as one of the “Books of the Year” for 2009), Against Excess: Drug Policy for Results (winner of the Wildavsky Prize of the Policy Studies Organization for 1993, and Marijuana: Costs of Abuse, Costs of Control. With Jonathan Caulkins and Angela Hawken, he co-wrote Drugs and Drug Policy: What Everyone Needs to Know, and (with those co-authors and Beau Kilmer) Marijuana Legalization: What Everyone Needs to Know. 


Mark Kleiman grew up in Baltimore where he attended local public schools. He graduated from Haverford College (B.A. in political science, philosophy, and economics, magna cum laude), before attending the John F. Kennedy School of Government at Harvard University, where he received his Master of Public Policy degree in 1974 and a Ph.D. in Public Policy in 1983. 


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