A fascinating study published last year that I only just stumbled across thanks to Mike Ashton:

The effect of marijuana scenes in anti-marijuana public service announcements on adolescents’ evaluation of ad effectiveness is the study and it’s worth reading the whole thing.

The take home message:

The analysts concluded that their most consistent findings related to the presence of scenes showing cannabis or its use. Youngsters unlikely in any event to use the drug reacted well to anti-cannabis ads regardless, but those the ads most needed to deter – the ones most likely to use the drug – saw the ads overall as less effective, and especially those which featured the drug or its use. Neither were they swayed by what young people in general saw as stronger anti-cannabis arguments; on one important measure, they actually reacted more negatively to strong-argument ads. The lesser relevance of argument strength may have been due to the fact that in respect of cannabis deterrence, youngsters saw all the arguments as only moderately convincing. These findings caution against featuring images of cannabis or its use in anti-drug campaigns.

Are you surprised by any of that? I’m not particularly…