Cannabis in Aotearoa New Zealand

The Prime Minister has asked Juliet to provide an accessible summary of the evidence to inform the cannabis referendum. Our expert panel has been charged with pulling together as much information as we can about the impacts of cannabis, and to present it in a way that is easy to understand for voters.

Aspects of the work will include, but not necessarily be limited to, analysing the impacts of cannabis use in the current legal framework, what changes have occurred overseas when access to cannabis is decriminalised or legalised,  the confidence level around the evidence base, and how applicable is it is to Aotearoa New Zealand.

Values Statement

The work of the panel will be characterised by rigour, respect, openness, collaboration, inclusivity and integrity. We recognise the significance of culture, including te Tiriti o Waitangi. We strive to acknowledge our biases and limitations, synthesise the evidence and expose the gaps.

Project details

The cannabis project is underway. We are currently analysing and collating the evidence-base to summarise and present in a way that is easy to understand for voters. This information will be uploaded to this page as we go – so check back for updates.

Project scope

The Terms of Reference set the project scope. The evidence-base will fall within the following five workstreams:

  • What are the personal and societal harms from recreational cannabis use?
  • What are the potential non-medical benefits of recreational cannabis use? (e.g. reduction in
    costs for the justice system)
  • What is the evidence base surrounding impacts of decriminalization of recreational cannabis
    use, and how might the impacts be monitored?
  • What is the evidence base surrounding the impacts of legalisation of recreational cannabis use,
    and how might the impacts be monitored?
  • What is the confidence level around the evidence base and where are there important gaps in
    our knowledge?
Meeting agendas and minutes

So far, we have had one full panel meeting and you can see the minutes for this meeting below.

  • Meeting 1 (9 September 2019) Minutes

Panel members

You can read more about the panel members by following the links or by reading blurbs below.

Our first panel meeting

Ngā mihi maioha ki te rōpū nei. He kaupapa whakahirahira, hei whakarongo ki te whaka kotahi o ngā whakaaro kē. Here’s a quick reflection on our first cannabis panel meeting.

Panel members and OPMCSA staff at the first panel meeting. From left to right: Juliet Gerrard, Joseph Boden, , Tracey McIntosh, David Newcombe, Hinemoa Elder, Chris Wilkins, Khylee Quince, Benedikt Fischer, Doug Sellman, Michelle Glass, Tamasailau Suaalii.

Panel members and OPMCSA staff at the first panel meeting. From left to right: Juliet Gerrard, Joseph Boden, , Tracey McIntosh, David Newcombe, Hinemoa Elder, Chris Wilkins, Khylee Quince, Benedikt Fischer, Doug Sellman, Michelle Glass, Tamasailau Suaalii.

Cannabis press gallery

We have pulled together press items that provide information relating to the cannabis referendum which you can see here. Additional information will be added as information is forthcoming.

Weeding through the evidence on cannabis

Kia ora koutou

This month we are kicking off work to develop a short, accessible summary of the evidence base surrounding cannabis. Our expert panel has been charged with pulling together as much information as we can about the impacts of cannabis, and to present it in a way that is easy to understand for voters, ahead of the referendum. This will provide a summary to help New Zealanders who want access to reliable information, endorsed by experts from across disciplines.

In our cannabis project, the panel’s terms of reference sets out the scope of the work. Broadly speaking, the work will cover:

  • the health, social, and criminal justice impacts of cannabis use in the current legal framework in Aoteoaroa New Zealand
  • the evidence for what changes have occurred overseas when access to cannabis is decriminalised or legalised
  • the confidence level around the evidence base, and how applicable is it is to Aotearoa New Zealand

It’s important for New Zealanders to make up their own minds about how to vote, so we won’t be making any recommendations. This is about distilling a broad range of complex research into a useful resource, and of course we’ll be including a full bibliography so that anyone who wants to dig deeper can easily do so.

Aotearoa New Zealand has a collection of amazing researchers in cannabis research, more than could possibly fit around our table. So how did we choose? Firstly, we wanted our panellists to be recognised experts, which means researchers who have published on cannabis and related issues and have deep practical knowledge of its impacts on society. We chose people who are independent of government and industry, and who represent Aotearoa New Zealand’s diversity. Have a look at their biographies here. A huge thank you to all of them for giving their time to this important mahi. We will draw on others in our community to referee the work as we proceed.

The panel is co-chaired by myself and Professor Tracey McIntosh, and we started proceedings on a high this week, with a lively all-day discussion. Most of the panellists are actively engaged in this public debate, and will continue to be so as we work, as individuals.

As someone new to this field, I have entered this project with a genuinely open mind and no fixed view of where I personally will land in the referendum. There is a lot of evidence to digest about the degree of harm that cannabis does, and doesn’t, cause to individuals, whanau and communities, and importantly the differential harm to specific communities. There are stories from overseas to learn from, but none that apply directly to our situation here. One thing that was immediately clear in our first meeting was that the evidence won’t be clear cut, so our most valuable contribution may well be a clear explanation of how confident we are in the data.

We will be uploading information onto the website as we go – so check back for updates.

Ngā mihi

Panel Biographies (in alphabetical order)

Associate Professor Joseph Boden

Joseph Boden is a member of the Department of Psychological Medicine at the University of Otago, Christchurch. Originally earning a PhD in experimental social psychology, Dr. Boden held university lectureships in the UK and Australia before coming to New Zealand in 2002. Since 2005 he has been employed as a researcher on the long-running Christchurch Health and Development Study (CHDS), a longitudinal study of over 1000 New Zealanders born in Christchurch in mid-1977. In 2015 Dr. Boden was appointed Deputy Director of the CHDS. Dr. Boden’s research interests include the psychosocial causes and consequences of substance use, abuse, and dependence, mental health and substance use epidemiology, and the social and psychological determinants of maladaptive behaviour including aggression and violence, amongst other topics.

Professor Benedikt Fischer

Benedikt Fischer (PhD, University of Toronto) is the inaugural Hugh Green Foundation Chair in Addiction Research and Professor in the Schools of Population Health & Pharmacy, Faculty of Medical and Health Sciences, University of Auckland, New Zealand. He holds additional academic appointments with the Department of Psychiatry, University of Toronto, Canada; the Centre for Applied Research in Mental Health & Addiction (CARMHA), Simon Fraser University, Vancouver, Canada; and the Department of Psychiatry, Federal University of Sao Paulo (UNIFESP), Brazil. Prior to his moving to New Zealand in 2018, Professor Fischer held senior academic appointments in Canada, as Senior Scientist at the Centre for Addiction & Mental Health and the Addiction Psychiatry Chair at the University of Toronto (until 2018) and as the CIHR/PHAC Applied Public Health Research Chair and Director of CARMHA at Simon Fraser University, Vancouver (2008 – 2014).

Professor Fischer’s scientific work focuses on the social, behavioural and health outcomes of, and evidence-based prevention and treatment interventions for psychoactive substance use and related co-morbidities (e.g., mental health, pain, infectious disease) in an interdisciplinary, public health-oriented framework. His scientific work is strongly geared towards knowledge translation for improved interventions, systems and policy. For more than two decades, he has made major scientific contributions to public health-oriented cannabis control and interventions, including as lead-author of the internationally adopted ‘Lower-Risk Cannabis Use Guidelines (LRCUG)’.

Professor Fischer acted as Senior Science Advisor to the Canadian government for the development of its cannabis legalization framework, and has advised other governments (e.g., Uruguay) on cannabis and health policy issues. Professor Fischer has some 375 scientific publications in his name; he was a founding lead investigator of the Canadian Research Initiative in Substance Misuse (CRISM) and his work has been extensively funded by leading national and international funding agencies (e.g., the Canadian Institutes of Health Research). He is a co-author of several international books: ‘Drug Policy & the Public Good’ (Babor et al., 2018) and ‘Cannabis Policy: Moving Beyond Stalemate’ (Room et al., 2010). He has served in science-advisory roles for preeminent institutions (e.g., CIHR’s Institute of Neuroscience, Mental Health and Addiction; the Mental Health Commission of Canada, Health Canada). Professor Fischer is a frequent and sought-after expert speaker and commentator to academic, media and general public audiences on his topics of expertise.

Professor Tracey McIntosh (Co-Chair)

Tracey McIntosh, MNZM is of Ngāi Tūhoe descent and is Professor of Indigenous Studies and Co-Head of Te Wānanga o Waipapa (School of Māori Studies and Pacific Studies) at the University of Auckland. She was the former Co-Director of Ngā Pae o te Māramatanga New Zealand’s Māori Centre of Research Excellence. She previously taught in the sociology and criminology programme at the University of Auckland. She was a Fulbright Visiting Lecturer in New Zealand Studies at Georgetown University in Washington D.C. and lectured at the University of the South Pacific in Fiji. She has sat on a number of assessment panels including PBRF panels ( Māori Knowledge and Development and Social Sciences) Marsden Social Science Panel, Rutherford Discovery, James Cook Fellowship and Health Research Council Panels. In 2012 she served as the co-chair of the Children’s Commissioner’s Expert Advisory Group on Solutions to Child Poverty.​ In 2018-2019 she was a member of the Welfare Expert Advisory Group and Te Uepū Hapai i te Ora- The Safe and Effective Justice Advisory Group. She sits on a range of advisory groups and boards for government and community organisations. She currently delivers education and creative writing programmes in prisons.​

Her recent research focused on incarceration (particularly of Māori and Indigenous peoples), gang whānau issues and issues pertaining to poverty, inequality and social justice.

Associate Professor Khylee Quince

Khylee Quince is from the iwi of Te Roroa/Ngapuhi and Ngati Porou. She teaches Criminal Law, Advanced Criminal Law and Youth Justice. Her research interests lie within those fields; in particular Māori and the criminal justice system, tikanga Māori and the law, restorative justice and alternative dispute resolution, Māori women and the law, indigenous peoples and the law.

Prior to joining the University of Auckland’s Law Faculty in 1998, Khylee practiced in criminal and family law for three years. Khylee is now Associate Head of School and Director of Maori and Pacific Advancement at the AUT School of Law. She is also a trustee on the New Zealand Drug Foundation.

Associate Professor Tamasailau Suaalii-Sauni

Tamasailau Suaalii-Sauni currently teaches in the Criminology Programme. She completed both undergraduate and postgraduate university studies at the University of Auckland. She held teaching fellow, research fellow, lecturing and deputy director positions within the University of Auckland’s Department of Sociology, Department of Maori and Pacific Health, and Centre for Pacific Studies from 1998-2008. She moved to the University of Otago to take up a senior research fellow position with the Centre for International Health based at the National University of Samoa in Apia from Nov 2008-July 2011. After which she took up senior lecturer and programme director positions with Victoria University of Wellington’s (VUW) Va’aomanu Pasifika Unit from 2011 to 2016. Tamasailau returned to the University of Auckland in Oct 2016 as Associate Professor in Sociology/Criminology, School of Social Sciences. As well as working for the university sector, Tamasailau has also held honorary and part-time senior researcher and programme evaluator roles in the state and private sector: mainly with the Waitemata District Health Board’s Clinical Research and Resource Centre (2003-2008), and with (as co-director) Pacific Research and Development Services Ltd (1998-2003). Tamasailau was a member of the Superu and VUW central ethics committees.

Dr Hinemoa Elder

Ko Pārengarenga te moana
Ko Tawhitirahi te maunga
Ko Awapoka te awa
Ko Te Aupouri, ko Ngāti Kurī, ko Te Rarawa, ko Ngāpuhi nui tonu oku iwi
Ko Hinemoa taku ingoa

Hinemoa Elder is a Fellow of the Royal Australia and New Zealand College of Psychiatrists and has been a consultant child and adolescent psychiatrist since 2006. Dr Elder is the Māori Strategic Leader for the Centre of Research Excellence (CoRE) for the Ageing Brain. In addition to her initial medical qualifications, Dr Elder has a PhD (Massey University, 2012) and is former HRC Eru Pomare Post-Doctoral Fellow (2014-18) in which she developed a novel recovery approach grounded in Te Ao Māori (Māori world view), for Māori with traumatic brain injury, their whānau (extended families) and professionals which is now being used in community rehabilitation services. She continues to work clinically as a neuropsychiatrist and youth forensic psychiatrist. She is an expert in the areas of psychological trauma and cultural psychiatry. She also currently works at the Child and Family Unit, Starship Hospital.

Dr Elder has served on several Ministry of Health reference groups. She is a deputy psychiatrist member of the NZ Mental Health Review Tribunal and a Specialist Assessor under the Intellectual Disability (Compulsory Care and Rehabilitation) Act 2003. She is a member of the International Science Advisory Board to the National Science Challenge ‘E tipu e rea, a better start’.

Professor Michelle Glass

Michelle Glass took up the position of Head of the Department of Pharmacology and Toxicology and the University of Otago in July 2018, after 17 years at the University of Auckland, including six years as the Head of Pharmacology and Clinical Pharmacology. As a molecular pharmacologist, Professor Glass’ research focuses on the expression, function and molecular pharmacology of the cannabinoid receptors and their potential role in treatment of neurodegenerative diseases.

Following her PhD, in which she mapped the then newly discovered cannabinoid CB1 receptor in the human brain, she worked on cannabinoid receptor signalling as a postdoctoral Fellow at the National Institutes of Health in Bethesda, Maryland for five years before returning to New Zealand in 2000 to take up a role as a Lecturer (and researcher) within the Department of Pharmacology at the University of Auckland. She has published over 90 papers on cannabinoids, and numerous book chapters.

Her contributions to the field have been acknowledged by an early career award from the International Cannabinoid Research Society in 2009 and by election to President of this society in 2015.

Dr David Newcombe

David Newcombe is Academic Director of postgraduate addiction programmes and Head of the Section of Social and Community Health in the School of Population Health, and Associate Director of the Centre for Addiction Research. He has been working in the addiction sector for over 20 years in various clinical and research roles both in Australia and New Zealand. Prior to moving to New Zealand, David was Senior Project Manager at the WHO Collaborating Centre for Research in the Treatment of Drug and Alcohol Problems at the University of Adelaide where he managed an international multisite evaluation of opioid pharmacotherapies for the treatment of opioid dependence and the Australian site of the validation of the WHO Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) study.

His current research interests include: screening for problematic substance use and assessing the efficacy of brief interventions in different at risk groups; the clinical pharmacology and psychopharmacology of drugs of abuse; and clinical effectiveness of pharmacotherapies used to treat alcohol and drug problems.

Professor Doug Sellman

Doug Sellman, MBChB PhD FRANZCP FRAChAM, is a psychiatrist and addiction medicine specialist. He is recognised as a national leader in the addiction field in New Zealand having been Director of the National Addiction Centre (NAC), University of Otago Christchurch from 1996-2017 and contributing to the development of a highly successful national postgraduate training programme in the area of addiction and co-existing disorders. He has been involved in a broad range of addiction-related research projects with over 100 peer-reviewed publications involving alcohol, cannabis, opioids, nicotine, methamphetamine, gambling and food, primarily from a treatment perspective.

Over the past 15 years this work has turned increasingly towards public health and prevention. He was promoted to a Personal Chair within the University of Otago in 2006, and in 2009 was one of the initiators of Alcohol Action NZ, a medically-led advocacy group for alcohol law reform. His clinical work was in adult addiction services from 1987-1994 and then in youth services from 1994-2014. He is now partially retired and runs a small private practice with a special focus on food addiction and obesity, while continuing research and teaching work at the NAC.

Associate Professor Chris Wilkins

Chris Wilkins is the leader of the drug research team at SHORE & Whariki Research Centre, College of Health, Massey University. Chris Wilkins has research expertise in drug trends, drug markets, public health, and drug policy. Over the past twenty years he has completed a range of studies of drug use in New Zealand with particular focus on methamphetamine, cannabis, legal highs, ecstasy and the non-medical use of pharmaceuticals. Chris Wilkins has published numerous journal articles on drug use, contributed to three books and regularly reviews manuscripts for Addiction, the International Journal of Drug Policy, Drug & Alcohol Review and Drug and Alcohol Dependence. Chris Wilkins has been an invited speaker at international meetings convened by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA), and at the United States National Institute for Drug Abuse Community Epidemiology Working Group (CEWG). He regularly presents papers at the annual meetings of the International Society for the Study of Drug Policy (ISSDP).


  Phone: + 64 9 923 6318

Mailing Address

Office of the Prime Minister's Chief Science Advisor
The University of Auckland
Private Bag 92019
Victoria Street West
Auckland 1142
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