Outlawing psychoactive drugs amounts to the worst case of scientific censorship in modern times, leading scientists have argued.

UN conventions on drugs in the 1960s and 1970s have not only compounded the harms of drugs but also produced the worst censorship of research for over 300 years. This has set back research in key areas such as consciousness by decades and effectively stopped the investigation of promising medical treatments, the researchers say.

The paper is written by Professor David Nutt of Imperial College London and Leslie King, both former government advisors, and Professor David Nichols of the University of North Carolina at Chapel Hill.

The possession of cannabis, MDMA (ecstasy), and psychedelics is stringently regulated under national laws and international conventions dating back to the 1960s.

“The decision to outlaw these drugs was based on their perceived dangers, but in many cases the harms have been overstated and are actually less than many legal drugs such as alcohol,” said Professor Nutt, Edmond J Safra Professor of Neuropsychopharmacology at Imperial College London.

“The laws have never been updated despite scientific advances and growing evidence that many of these drugs are relatively safe. And there appears to be no way for the international community to make such changes.”

The illegal status of psychoactive drugs makes research into their mechanisms of action and potential therapeutic uses, for example in depression and post-traumatic stress disorder (PTSD), difficult and in many cases almost impossible, the researchers say.

Political motivation

“This hindering of research and therapy is motivated by politics, not science,” said Professor Nutt. “It’s one of the most scandalous examples of scientific censorship in modern times. The ban on embryonic stem cell research by the Bush administration is the only possible contender, but that only affected the USA not the whole world.”

Professor Nutt and his colleagues point out that the limitations of cannabis research have had a very harmful impact on UK pharmaceutical productivity. Although many of the psychoactive elements of the cannabis plant were discovered in the UK, developing them into medications has been severely hampered by excessive regulation.

They argue that the use of psychoactive drugs in research should be exempted from severe restrictions. “If we adopted a more rational approach to drug regulation, it would empower researchers to make advances in the study of consciousness and brain mechanisms of psychosis, and could lead to major treatment innovations in areas such as depression and PTSD,” Professor Nutt said.

The call for reform has been endorsed by the British Neuroscience Association and the British Association for Psychopharmacology, and the researchers are also seeking support from other academic organizations.