Alex Berenson & # 39; s Tell your children: the truth about marijuana, mental illness and violence begins early with a personal anecdote: one evening, Jacqueline Berenson, a forensic psychiatrist and Berenson's wife, remembered a case where a man "cut his grandmother into pieces or set fire to his apartment." At a certain point in the discussion, Jacqueline remarked, "Of course he was high, he smoked pot all his life."

As a journalist, this aroused Berenson's curiosity. He claims that he previously considered marijuana as relatively innocent. But here was his wife, with all her expertise, linking marijuana to a gruesome crime. When he pushed back, his wife told him to look at the scientific evidence. He did that. The result is the book in which that conversation is now being re-told – a book that has received widespread favorable coverage in CNBC, the New Yorker, Mother Jones and the Marshall project, and landed eds by Berenson about his findings in New York Times, the Wall Street Journal and the Philadelphia Inquirer.

His central argument can best be summarized in some short lines later in the book: "Marijuana causes psychosis Psychosis causes violence The obvious implication is that marijuana causes violence."

I could have found this argument convincingly. Over the years, I have become increasingly skeptical about the legalization of medicines, as I have reported on the opioid epidemic (caused by legal opioid painkillers), alcohol and tobacco. I have written about the risks for marijuana who are worthy of taking seriously, even if you think that legalization is ultimately a better policy than a ban. I myself stopped using marijuana, partly because my husband had several experiences where pot seemed to flare up his anxiety disorder.

But when I read Berenson's book, it was impossible to escape from it, while a compelling reading was written by an experienced journalist, but it is essentially an exercise in collecting cherries and presenting correlation as a cause. Observations and anecdotes, not rigorous scientific analyzes, form the core of the book's claim that legal marijuana will cause – and in fact even cause – an enormous increase in psychosis and violence in America.

The book focuses largely on horrific anecdotes of violent crimes committed under the influence of marijuana, the kind of "reefer madness" stories that the authorities and the media relied on when they first banned cannabis in the 20th century.

Berenson uses these anecdotes and limited data to claim that the use of heavy marijuana, stimulated by the legalization of pot in different American states, already leads to a "black flood of psychosis" and "red tide of violence." He warns that things only get worse as the legal pot industry grows, with an incentive to suppress heavy rules for cannabis.

In an example, he cites a recent, massive assessment of the evidence on the benefits and harm of marijuana from the national academies of sciences, engineering and medicine, which claim the report, about the link between marijuana and psychosis, "the problem explained. "

But I read the report and wrote about it for Vox when it came out. Far from explaining this issue "regulated", the National Academies' report was extremely cautious, warning that marijuana's and marijuana addiction-related to psychosis can be "multidirectional and complex." Marijuana can not cause psychosis; something else can cause both psychosis and pot use. Or the cause may go the other way: psychotic disorders can lead to the use of marijuana, perhaps in an attempt to self-medicate.

"In certain societies," says the report, "the incidence of schizophrenia has remained stable over the past 50 years, despite the introduction of cannabis in that environment."

Berenson does not mention this when discussing the report. He only cites the parts of the report that are favorable to his dissertation – a poor service for the massive, rigorous work of the 16-man committee of scientists who, with thousands of studies, took the risk for the review.

And this is representative of the book as a whole.

Berenson says he named the book Tell your children as an ironic joke to his critics, because it is the original name of the infamous movie Reefer Madness (1936), which shows people who behave violently after the use of marijuana. But the further I got into the book, the more it seemed that Berenson was imitating the strategy he wanted to mock. Tell your children is Reefer Madness 2.0.

There are concerns about marijuana and how legalization is exercised. As the report of the National Academies makes clear, there is still a lot about cannabis that we just do not know, including its drawbacks and benefits. There is a risk of commercializing another product that is addictive to some and may be harmful to others in other ways, and there may be better ways to legalize or regulate pot that minimizes those risks than we do. do it today.

But Berenson's book, with his sensational assertions and his untidy analysis of the evidence, does not really address these concerns. Tell your children claims to inform his readers of the "truth" about marijuana, but instead he misleads them repeatedly.

A marijuana executive prepares for the first day of recreational sales in Denver, Colorado.

A marijuana executive prepares for the first day of recreational sales in Denver, Colorado. R.J. Sangosti / Denver Post via Getty Images

Berenson overestimates the evidence for the link between marijuana and psychosis

Much of Berenson's book focuses on the history of schizophrenia, psychosis and the legalization of marijuana. But the essence of Berenson's thesis is an alleged connection between marijuana, psychosis and violence, and an argument that legalization, and the greater degree of cannabis use that goes with it, will create more violent crime in the US.

Berenson seizes back early to the initial wave of cold-blooded madness, looking at the reception of marijuana at the end of the 19th and the beginning of the 20th century in Mexico and India. He claims that if Mexico and India, separated by 9,000 miles, independently concluded that marijuana causes psychosis, should not we take that seriously?

He writes: "In 1901, for example, a newspaper reported about a man who attacked strangers on the street and then" & # 39; turned around and with bites he tore his own arms apart until a straitjacket caught him … he was crazy under the influence of marijuana. & # 39;

Mexicans "had no cultural reason to view marijuana negatively," he adds later. "Yet they did it."

Berenson quotes for his information about Mexico Home grown: marijuana and the origin of Mexico's War on Drugs by historian Isaac Campos of the University of Cincinnati.

I know Campos personally. He taught me the history of the war on drugs and drug policy when I studied at the University of Cincinnati. I read the book of Campos very early in my growing interest in drug policy, and although my memory at the beginning of 2010 was a bit vague, I knew something was wrong with what Berenson wrote. I emailed Campos to confirm my suspicion.

Campos warned that he reads only two photocopied pages from the Berenson book in which he is quoted. But on that basis he said that Berenson had misrepresented his argument. It is not at all clear, he said, that the use of marijuana alone caused the violent outbreaks, even though it was a widespread belief in Mexico at the time.

Marijuana was mostly used in & # 39; the most marginal environments in Mexico, especially prisons and military barracks, both extremely inhospitable and violent environments & # 39 ;, Campos told me. And at that time it was generally believed that marijuana caused insanity and violence, which may have created a self-fulfilling prophecy, because such behavior was essentially considered typical while stoned. Couple this with the fact that marijuana can cause real paranoia and anxiety (as everyone who is used to, can confirm) and you get bad stories.

But is marijuana the fault, the circumstances of its use, or a combination of these and other factors? It is at least a much more complicated story than the one-sided representation of Berenson.

Photographs of marijuana plants, around the 1890s.

Photos & # 39; s from Marijuana Plants, around the 1890s .Universal sculpture group via Getty Images

There is a similar story with India, where asylum statements were used to claim that marijuana led people to psychosis. Berenson acknowledges a government report that appeared at that time, in 1894, when the asylum reports were found to be seriously inadequate; many of them, for example, are cases related to opium or alcohol, not to marijuana. But Berenson rejects this evidence and then focuses on reports, including the wrong asylum cases, which support his position.

He quotes several studies that he suggests adding scientific weight to his claims. He spends a lot of time on Sven Andréasson, a researcher from Sweden who entered in 1987 The Lancet one of the first major studies to establish a strong link between marijuana and schizophrenia.

"Based on his data and later findings, Andréasson says he believes that cannabis accounts for 10 to 15 percent of cases of schizophrenia," Berenson writes. "Few people develop schizophrenia solely because of smoking," he says, but many who would not be ill do so because marijuana pushes their fragile brains over the edge. "

Berenson continues in this direction, profiling researchers and studies from all over the world, from the UK to New Zealand, giving the impression of establishing a link between marijuana and psychosis. He also cites some anecdotal examples of people who have recently experienced mental health problems, including Kanye West, and suggests, without much evidence, that marijuana was the cause of their slumps. ("Nobody seemed to connect [West’s] diagnosis for his cannabis use, "Berenson complains.)

It is worth noting that you can easily do this kind of thing in the opposite direction – look up some research through Google that show that marijuana does not cause psychosis or related disorders. A study from 2018 published in Nature Neurosciencesuggested, for example, that it is more likely that schizophrenia leads to the use of marijuana (possible to cope with or to cope with self-medication), and not the other way around.

But we do not have to do this kind of cherry picking. Tighter reviews of the evidence have provided much more clarity than a cursory glance at the evidence from a journalist – or Berenson if I can ever give it. That is where the report of the National Academies comes.

The report is very cautious in its findings. It notes that there is "substantial evidence" of a relationship between marijuana and psychotic disorders, and that the association is dose-dependent – a greater risk corresponds to a heavier use of marijuana. But the report also notes that the explanation for the association is unclear.

Berenson is in favor of the idea that pot causes and worsens psychosis and psychotic disorders. However, in the report of the National Academies, other possibilities are plausible: perhaps psychosis or psychotic disorders lead to marijuana, or a third factor – for example genes or environment – leads to psychosis and marijuana use. It can be a combination of all these factors.

The conclusion, if there is: "This is a complex issue, which certainly warrants further investigation." In other words, we do not know it yet.

Apart from that, the national academies have also analyzed studies on how marijuana affects the symptoms of psychotic disorders. This study was more limited, although a number of data showed that a history of the use of marijuana could actually improve the cognitive performance of people with psychotic disorders (which could explain why people with psychotic disorders are themselves medicated with weed, if that is the case). case). But the report finally concluded that the evidence in this area was "limited" to "moderate", so more research is needed.

Unlike Berenson & # 39; s book, the report was conducted by more than a dozen rigorous scientists with expertise in empirical research and analysis. They looked at many more studies than Berenson quotes in his book. Yet their conclusions are much tamer than those of him – certainly not "arranged," as he writes. That is worth taking seriously.

This does not exclude Berenson's claims. It is possible that he is right to some extent, and marijuana causes or worsens psychosis or psychotic disorders. But now his claims are far ahead of the evidence.

Berenson reaches out with his marijuana-violence argument Reefer Madness area

About Berenson's case is even thinner, with large parts of the book devoted to anecdotes of people who commit violent crimes, possibly under the influence of marijuana.

For example, he writes about a personal trainer in Tennessee who killed his former boss in June 2018 with an ax. Berenson suggests that the attack was caused by marijuana, citing a previous social media post in which the attacker discussed cannabis use.

That is it. Although Berenson makes an explosive claim (one that the media and police have not reported when the case was in the news, as far as I can tell), that's all he gives us to support his suggestion that marijuana has caused the attack .

This happens again and again. Berenson raises the case after a cruel crime case, and then argues that the attacker had a history of marijuana use or used cannabis shortly before the attack. There is no evidence that marijuana caused the attack; Berenson recognizes this factually and writes that he & # 39; could not always be sure that cannabis played a role & # 39 ;. But when he brings things together, he tries to prove that there are too many of these stories to be coincidence – indicating that marijuana is causing massive psychotic violence.

"Do you want more cases? Because there is unfortunately enough," he concludes. "The black tide of psychosis and the red tide of violence rise together on a green wave, slowly and stably and surely."

A poster advertising Reefer Madness.

A poster advertisement Reefer Madness.Hulton Archive via Getty Images

We have seen this before. At the end of the 19th century and the beginning of the 20th century, when marijuana was introduced in new parts of the US, the media and government officials published a lot of reports that exaggerated the risks of cannabis. They linked violent crimes – often involving immigrant perpetrators – to the previous use of marijuana. These reports resulted in Reefer Madness, the 1936 film and the Marijuana Tax Act of 1937, which was actually the first federal ban on marijuana.

Berenson's lecture from case to case is very similar to the previous panic. There is no consideration about how, for example, the circumstances surrounding a person's pot use may play a role, as has probably happened with the Mexico cases. Perhaps the reports are defective, as was the case with asylum cases in India. Or maybe the attackers were not driven to weed but they tried to deal with psychological problems that drove them to violence through the use of marijuana. We do not know.

By the way, in a country where in 2017 there were more than 800,000 heavy attacks and more than 17,000 murders and non-negligent death victims, and where at least 41 million people used marijuana that year, and even dozens of cases over the years on the drug. linking is not convincing evidence.

Berenson tries to support these stories with a few studies on marijuana and violence. It is true that some individual studies have found a connection, although many contradictory studies have not done so. That is why it is better to rely on large, rigorous reviews of the evidence when evaluating data.

Such an assessment exists: in 2013, one was conducted by the RAND Drug Policy Research Center, commissioned by the Office of National Drug Control Policy. It concluded that "marijuana use does not cause violent crime and that the link between marijuana use and property crime is thin."

Probably the most provocative claim in Tell your childrenBerenson tries to claim that the pot is already causing a peak in violence. Referring to the same data to which he referred in his opinion in the New York Times, he suggests that the first four states that legalized cannabis – Alaska, Colorado, Oregon, and Washington – then saw a massive increase in violent crimes, which he claims to be higher than a nationwide increase in violent crimes in the same span of time.

Here are his details about the state of Washington:

In 2013, Washington had 160 murders and approximately 11,700 heavily armed attacks, according to data on the state that the Washington Association of Sheriffs & Police Chiefs is providing to the FBI for its annual national crime report. In 2017, the state had 230 murders and 13,700 heavily armed attacks – an increase of about 44 percent for killings and 17 percent for severe ill-treatment. This increase far exceeded the national increase in crime. The killings rose about 20 percent at national level from 2013 to 2017, and aggravated attacks increased by about 10 percent.

Berenson does not dig into the possible causes and differences. There is no serious attempt to erase disturbing variables, with only a vague mention of a kind of "statistical analysis." The correlation between marijuana legalization and the increase in violent crimes is given – and repeated throughout the book, as well as The Op-eds of Berenson – as if the truth is obvious.

But as the old saying goes, correlation is not a cause. Aaron Carroll, a pediatrician and researcher at the Indiana University School of Medicine, made this point on Twitter, pointing out that there is a link between the sale of organic food and autism, but no one seriously believes that these two are related.

When it comes to marijuana and violence, you can also draw correlations in the opposite direction. Mark Kleiman, an expert in drug policy at New York University, told the New York magazine: "Cannabis use, and especially heavy cannabis consumption, has been on the rise since 1992. In that period, national murder rates have dropped by more than 50%. . "

Just as with the marijuana psychosis link, the mess of correlation and causality is the reason why more rigorous scientific evaluations are needed. We have that: Benjamin Hansen, an economist at the University of Oregon, compiled an analysis that was meters what the murders of Colorado and Washington would be if they had not legalized marijuana.

His conclusion: "Although it is true that the murder rates in CO and WA were higher than those for the whole country, the murder rates in Colorado and Washington were actually lower than the predicted figures would have been for the trends in killings of 2000-2012, "what is almost complete before they legalized marijuana. He added, "This suggests that at best we can not conclude that legalization of marijuana increases violence, and perhaps there can also be minor negative effects."

On the other hand, perhaps the lack of evidence that legalization had a big effect on violent crimes is not very surprising – based on Berenson's confession early on in the book, where he gives a number of figures for what he expects the effects to be. of marijuana are on psychosis and violence.

On the basis of work by a Dutch epidemiologist Berenson estimates that "one extra person in 250 may develop a psychosis through cannabis use" in countries with frequent use. He writes: "The United States is a big country." About 40 million Americans were born in the last decade, and an increase of 0.4 percent in psychosis would mean that by 2040 about 160,000 of these children will have a debilitating mental illness in about 2040. Many thousands of them will end up committing murder and other violent crimes. "

In the context of Berenson's book, this is meant to be really alarming – "thousands" of more violent crimes must sound scary. But if you consider that there are currently 330 million people in the US and 1.2 million violent crimes in just one year at the national level, those "thousands" start looking less worrying in a few decades. It is a fraction of a fraction of one percent of all violent crimes in America.

This is the worst case scenario – a scenario that makes Berenson's flawed claims at first sight worthless – and it is by no means the end of the world. Intentional or not, Berenson undermines his own claims of mass violence.

Berenson is right that marijuana is not without risk

Berenson is right in one respect: it is true that marijuana is not harmless.

The assessment by the National Academies of the evidence also speaks about this. It found evidence that marijuana is linked to breathing problems (if smoked), car accidents, lagging academic and other social benefits and lower birth weight (if smoked during pregnancy).

There is also the risk of addiction. As Annie Lowrey reported for the Atlantic, federal surveys suggest that one in ten people who use marijuana become addicted. These are not claims from doctors or police. These are users who themselves report in national surveys that they have difficulty stopping marijuana use, even if this causes them to neglect their responsibilities and have other negative consequences for their lives.

In addition to the damage to individuals, excessive use and addiction are probably also bad for society. Jon Caulkins, an expert in drug policy at Carnegie Mellon University, told me: "At a certain level, we know that spending more than half of your waking hours for years and years does not increase the chances of winning a Pulitzer Prize or discover the cure for cancer. "

It remains unclear, based on federal and state data, or legalization of marijuana leads to more cases of addiction or other marijuana-related damage. But it is in any case worthwhile to keep an eye on, given the real risks.

There is also a lot we do not know about marijuana, including whether the much more powerful types of cannabis that people use today will create new problems that have not been seen before. More than anything else, this is what the National Academies report emphasized: we have a regrettable lack of data on this drug, even if we drastically change many policies around it.

On the other hand, Berenson makes good comments about the excessive benefits of medicinal marijuana. Although proponents claim that marijuana treats everything from Parkinson's disease to inflammatory bowel disease to epilepsy and PTSD, the evidence is very limited. The National Academies' analysis found "conclusive or substantial evidence" that cannabis can help with chronic pain, chemotherapy-induced nausea and vomiting, and patient-reported multiple sclerosis spasticity symptoms, but the use of marijuana for other conditions is limited to no scientific evidence. .

That is not nothing, but it is clear that medical marijuana proponents are far ahead of scientific evidence with their claims. To this end they make many of the same mistakes that Berenson does in his book.

A man smokes marijuana in a medical marijuana cooperative in San Francisco in 2004.

A man smokes marijuana in a medical marijuana cooperative in San Francisco in 2004. Austin Sullivan / Getty Images

There are also legitimate concerns about how the US legalizes cannabis

Berenson is explicit that he is now writing this because of legalization. At the end of his book, he fantasizes about the collapse of the marijuana movement, as in the 1970s when national decriminalization of marijuana seemed more and more certain. He writes that "at the end of the 1970s, once enough people experienced the effects of marijuana up close, the tide shifted almost immediately."

However, he also worries that it may be too late – that legalization is already creating a huge industry with a big financial incentive to exaggerate the benefits of marijuana, to downplay the risks and to fend off rules. He claims that "full legalization will generate billions of dollars for new investments in cannabis companies, making it even more difficult to impose restrictions."

This would not be a new result in America. With the tobacco, alcohol and opioid industries, money interests have done everything to downplay the risks of their products, even if tens of thousands (in the case of opioids and alcohol) or hundreds of thousands (in the case of tobacco). ) of Americans die every year.

But a complete ban has its own costs. Hundreds of thousands of people are arrested every year for marijuana in the US – possibly leading to a criminal record or imprisonment. Black Americans are arrested much more often, even though they use weed at comparable rates as white Americans. The black market for marijuana also effectively funds violent drug cartels and trafficking organizations around the world, allowing them to commit violence.

That is why Berenson calls decriminalization, when penalties for possession are reduced, but the sale remains completely illegal, "a reasonable compromise." He writes: "People should not be arrested or sent to prison for possession of marijuana.If they are stupid enough to smoke publicly, the police must take their joints and give them a ticket. to be caught smoking while in conditional release, they must be sent back to prison, but if they want to use it in the privacy of their own home, so be it. & # 39;

There are other options. A 2015 report from RAND mentioned a dozen alternatives to the standard ban. One of the possibilities: the legalization of property but not the sale (as Washington, DC and Vermont have done), through which government institutions are in charge of sales (as some Canadian provinces do, and as some states do, successfully with alcohol ), non-profit organizations to sell pot, or allow a handful of closely-controlled for-profit companies to participate.

A card with different options to legalize marijuana.

RAND Corporation

If we apply commercial legalization, governments can also use a harder approach than some states. They could impose higher taxes. They may need warning labels. They can limit marketing. They can prohibit certain products, such as foods that can appeal to children and are more likely to cause (non-fatal) overdoses. They could limit the strength of the doses. They could make systems that make it more difficult for users to consume too much.

All this means that there are real risks for marijuana, legitimate concerns about the current form of legalization that embraces America, and alternatives to what the country is doing alongside the wrong binary choice between prohibition and commercial legalization.

But there are ways to write about all these issues and still capture the nuance and details that they require. I recommend that Marijuana legalization: what everyone needs to know by Caulkins, Kleiman and Beau Kilmer, all of whom are true researchers and scientists of drugs policy. I do not recommend Berenson's book.

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