The Brown government is in danger of losing all its scientific advisers in a fascinating moment in which truth meets political and social prejudice. David Nutt, one of the government's chief advisers, was fired, in part, for the graph above which tries to assess the relative dangers of various drugs. Nutt assessed them on three variables:

a) the physical harm to the individual user caused by the drug; b) the tendency of the drug to induce dependence; c) the effect of drug use on families, communities and society. Within each category there are three components, leading to a nine-category matrix of harm, with scores of zero to three for each category. This is the final list based on that classification. In brackets is the classification given under the Misuse of Drugs Act, with Class A attracting the most serious penalties.

The Brits classify drug penalties according to the tree types A, B, and C. It's hard to read, so here are the drugs in order of harm, according to scientific studies, revealing how some drugs are categorized according to social attitudes rather than reality:

1. Heroin (Class A)

2. Cocaine (Class A)

3. Barbiturates (Class B)

4. Street methadone (Class A)

5. Alcohol (Not controlled)

6. Ketamine (Class C)

7. Benzodiazepine (Class B)

8. Amphetamine (Class B)

9. Tobacco (No class)

10. Bupranorphine (Class C)

11. Cannabis (Class B)

12. Solvents (Not controlled)

13. 4-MTA (Class A)

14. LSD (Class A)

15. Methylphenidate (Class B)

16. Anabolic steroids (Class C)

17. GHB (Class C)

18. Ecstasy (Class A)

19. Alkylnitrates (Not controlled)

20. Khat (Not controlled)

You immediately see that marijuana and ecstasy are far less dangerous than tobacco and alcohol. Ditto steroids - largely harmless if used properly. Nutt wonders why the government hires scientists if they refuse to abide by government policies:

My sacking has cast a huge shadow over the relationship of science to policy. Several of the science experts from the Advisory Council on the Misuse of Drugs (ACMD) have resigned in protest and it seems likely that many others will follow suit. This means the Home Office no longer has a functioning advisory group, which is very unfortunate given the ever-increasing problems of drugs and the emergence of new ones. Also it seems unlikely that any “true” scientist one who can only speak the truth will be able to work for this, or future, Home Secretaries.

Others have suggested a way forward: create a truly independent advisory council. This is the only realistic way out of the current mess.

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