Most notably perhaps, a team of researchers writing in the July 28, 2007 edition of the prestigious scientific journal The Lancet, boldly proclaimed that smoking cannabis could boost one’s risk of a psychotic episode by 40 percent or more.

Naturally, this alarmist rhetoric received wall-to-wall coverage by the mainstream press. Even more troubling, the supposed ‘pot-and-schizophrenia’ link was one of the primary reasons cited by British PM Gordon Brown, ex-Home Secretary Jacqui Smith and others as the impetus for reclassifying cannabis (from a verbal warning to a criminal offense punishable by up to five years in jail) in the United Kingdom.

Of course, there was a fatal flaw with The Lancet‘s argument — one that, oddly enough, every single MSM outlet failed to mention. Empirical data did not support the investigators’ hypothesis that smoking marijuana was associated with increased rates of schizophrenia or other mental illnesses among the general public — a fact that even the authors begrudgingly admitted when they declared, “Projected trends for schizophrenia incidence have not paralleled trends in cannabis use over time.”

Which brings us to 2009.

Two years after The Lancet‘s dire predictions, a team of researchers at the Keele University Medical School have once and for all put the ‘pot-and-mental illness’ claims to the test. Writing in a forthcoming edition of the scientific journal Schizophrenia Research, they compare long-term trends in marijuana use and incidences of schizophrenia and/or psychoses in the United Kingdom. And what do they find?

“[T]he expected rise in diagnoses of schizophrenia and psychoses did not occur over a 10 year period. This study does not therefore support the specific causal link between cannabis use and incidence of psychotic disorders. … This concurs with other reports indicating that increases in population cannabis use have not been followed by increases in psychotic incidence.”

Should we expect an apology — or even better, a change in policy — from the Gordon Brown regime any time soon? Or at the very least, will some sort of ‘correction’ be forthcoming from the mainstream news media?

I wouldn’t hold my breath.

In the months prior to the duo’s decision to call for the reclassification of cannabis — a move that increases the penalties for minor pot possession from a verbal warning to up to five years in jail — both politicians claimed that the potency of so-called British ‘skunk’ was skyrocketing out of control. Smith told the Commons that the strength of pot had increased “threefold” in recent years, while PM Brown told Reuters news wire, “[T]he cannabis on the streets is now of a lethal quality.”

Both implied that Parliament’s 2004 decision to downgrade pot possession to a verbal warning was responsible for the influx of supposed ‘triple-strength killer weed.’

Turns out Smith and Brown were full of it.

According to pot potency data collected by the UK’s Forensic Science Services and published by The Guardian newspaper, the average potency of THC in seized samples of British cannabis fell approximately 25 percent between 2004 and 2007.

Predictably, neither Smith nor Brown have issued any sort of public correction for their politically expedient, though thoroughly dishonest, remarks. Nor would one expect them to.

After all, for politicians, cops, and bureaucrats, lying about cannabis isn’t even considered lying — it’s simply viewed as part of the job. In fact, for the US Drug Czar, lying is actually mandated by law.

Of course, given the relative safety of adult cannabis use and given the utter failure of US criminal cannabis prohibition, it really can be no other way. Talking honestly about marijuana undermines federal drug policy so the only alternative for our elected officials is to lie — or say nothing at all. Troublingly, the leaders of both political parties have become adept at both.

Lest anyone think that science or reason guide modern cannabis policy, I present to you today’s announcement from British Home Secretary (and former pot smoker) Jacqui Smith calling on Parliament to increase pot penalties from a verbal warning — the current policy — to up to five years in jail.

Smith’s expected announcement (Watch the video here.) comes just days after British Prime Minister Gordon Brown — who has been afflicted with a severe case of ‘Reefer Madness’ since taking office last June — raved that consuming cannabis can be fatal, and that strict penalties on pot are necessary in order to “send a message” to young people that marijuana smoking is “unacceptable.”

Ironically, the Home Secretary’s formal announcement contradicts the official recommendations of Britain’s Advisory Panel on the Misuse of Drugs, which released its own report today finding that pot lacks the potential health risks of most other illicit drugs, and that its use is unlikely to trigger mental illnesses, such as schizophrenia.

It is the third time in six years that the Panel has demanded that legislators classify cannabis as a Class C ‘soft’ drug, with minor, if any, criminal penalties. Unlike Smith or Brown, the Advisory Panel consists of experts commissioned to evaluate and determine British drug policies — hence it’s hardly surprising that their findings would be totally disregarded by British bureaucrats.

For those readers who have not closely followed Britain’s ongoing pot policy debate, here’s a brief history lesson:

In January 2004, Parliament downgraded the legal classification of cannabis from a Class B drug (such as amphetamines or barbiturates) to a Class C drug (such as anabolic steroids) — thus allowing police to issue verbal warnings to minor pot offenders in lieu of arresting them. Since then, the following events have occurred:

One-third fewer Britons have been arrested for pot offenses;

Marijuana use by those age 16 to 20 years of age has fallen by 20 percent;

Fewer than ten percent of Britons now report using cannabis — the lowest percentage ever recorded.

In fact, the current policy has worked so well that the British Association of Chief Police Officers has announced that they will refuse to waste their time and resources arresting minor pot offenders — regardless of what Parliament decides.

So let’s review shall we. Gordon Brown wants to jail pot users to keep them from dying at the hands of weed — a stance so absurd that even the cops won’t go along with it. Home Secretary Jacqui Smith wants to jail pot users to keep them from losing their minds even though she herself smoked pot and is now one of the most powerful women in British politics. (Whether she is of sound mind remains debatable, I suppose.) The British Advisory Panel on the Misuse of Drugs thinks that Brown and Smith’s calls for reclassification are based on tabloid headlines in the Daily Mail rather than actual science, so they are dismissed as ‘know-nothings’ by the very same people who, quite literally, know nothing.

And that, my friends, is how we decide cannabis policy in 2008.

Any questions?