Former Drug Czar John Walters Spews Nonsense On Twitter; Cannabis Doesn’t Lower IQ

John Walters apparently likes Twitter:

Except, he needs to do more reading…

Then, a follow-up study published 6 months later in the same journal found that the Duke paper failed to account for a number of confounding factors: “Although it would be too strong to say that the results have been discredited, the methodology is flawed and the causal inference drawn from the results premature,” it concluded.

Now, a new study out from the University College of London provides even stronger evidence that the Duke findings were flawed. The study draws on a considerably larger sample of adolescents than the Duke research – 2,612 children born in the Bristol area of the U.K. in 1991 and 1992. Researchers examined children’s IQ scores at age 8 and again at age 15, and found “no relationship between cannabis use and lower IQ at age 15,” when confounding factors – alcohol use, cigarette use, maternal education, and others – were taken into account. Even heavy marijuana use wasn’t associated with IQ.


This conversation was a byproduct of Walter’s praise for Chris Christie’s comments about tax from legal Cannabis representing “blood money.” After being challenged by Nick Gillespie at Reason questioning why taxing alcohol is not “blood money”, he apparently blocked him.