Shock as new book exposes risks of marijuana

Green tide: According to the United Nations, 158.8 million people around the world use marijuana.

Just as opinion in rich societies seemed to be moving in its favour, marijuana has been blasted as a huge cause of mental illness and surging violence in a book causing a stir across the US.

It all started one evening, when writer Alex Berenson was talking to his wife. A psychiatrist, she was telling him about a horrific case she was handling, involving a young man who had killed a member of his family. “Of course, he was high, been smoking pot his whole life,” she said.

What does that one anecdote really mean? Could it be part of a wider trend? If so, is legalising marijuana a good idea?

These are the questions that Berenson attempts to answer in his incendiary new book: Tell Your Children: The Truth About Marijuana, Mental Health, and Violence.

In it, he makes two key arguments. One: that the long-term negative health impacts of the drug can be severe.

For example, a 2012 study found that those using cannabis by the age of 15 were four times more likely to develop schizophrenia. A 2017 study also linked the drug to psychosis and heightened risks of suicide, depression and social anxiety.

His second argument proved more controversial. According to Berenson, the terrible story told by his wife is not an isolated incident. “Because marijuana can cause paranoia and psychosis, and those conditions are closely linked to violence — it appears to lead to an increase in violent crime,” he writes.

He supports this claim with data which shows murder rates increasing in four American states which legalised the drug in 2014 and 2015.

But others say this does not add up. Reporter Jesse Singal points to FBI figures which show homicides increasing nationwide during that same period, regardless of whether states had legalised the drug or not. He called Berenson’s claims “misleading scaremongering”.

Then there is the bigger picture. “Cannabis consumption, and especially heavy cannabis consumption, has been on the rise since 1992,” claims drug expert Mark Kleiman. “Over that period, national homicide rates have fallen more than 50%.”

One thing is for sure: the push towards legalisation is getting stronger. Last year, Canada fully legalised the drug, and some MPs want Britain to do the same. What will the impact be if this happens? Only time will tell.

Up in smoke

So what is the right way forward? Many people insist that our current approach to drugs is not working. Criminal gangs sell marijuana to make fortunes, users are needlessly criminalised, and its potential medical benefits are wasted. Do the advantages of legalisation outweigh the risks? Would legalisation encourage more people to take drugs?

And what about society’s relationship with drugs at a more basic level. How different is marijuana to alcohol? Why are some substances acceptable, and others not? What drives people to seek drugs in the first place? These fundamental questions remain.

You Decide

  1. Should marijuana be legalised in the UK?
  2. Is it immoral to take drugs?


  1. As a class, list as many myths and rumours about cannabis as you can think of. Then go through them one by one and discuss which ideas you think are true, and which are false. Use the NHS link in Become An Expert to help.
  2. Read Alex Berenson’s piece in The New York Times, then Jesse Singal’s article for New York magazine. How does each writer use evidence to back up their argument? What language techniques do they use to make their writing persuasive? Who do you agree with more?

Some People Say...

“Words are, of course, the most powerful drug used by mankind.”

Rudyard Kipling

What do you think?

Q & A

What do we know?
There are just two countries in the world where marijuana has been fully legalised — Uruguay and Canada. It is legal in some American states, and decriminalised in several countries like Spain, Portugal and Brazil. As well as the harms discussed above, it also has medicinal properties. Parts of the drug can be used to treat chronic pain, epilepsy and multiple sclerosis.
What do we not know?
If marijuana will be legalised in the UK, and if so, when. In December last year, the former health secretary, Norman Lamb, urged the government to legalise the drug. Currently, however, there are no solid plans to do so. In places like Canada and the United States, we do not yet know what the long-term impact of sweeping legalisation is on public health and society.

Word Watch

A short story about a real incident or person.
Read the central arguments of the book in Alex Berenson’s New York Times piece by following the link in Become An Expert.
Symptoms include: hallucinations, delusions, unusual beliefs not based on reality, muddled thoughts and changes in behaviour. It is commonly thought of as a “split personality” disorder, however, this is not accurate.
A serious mental health problem in which sufferers are severely detached from reality.
Researchers stress that marijuana is not known to directly cause psychological disorders. So far, research has established a link between the two, but also acknowledges that other factors could be involved.
Jesse Singal
To find out more about his arguments against the book, read the New York magazine piece in Become An Expert.

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