A new study in the journal Addictive Behaviors provides further evidence that the federal government's anti-drug ads have a boomerang effect, making drug use more rather than less likely. The researchers showed two randomly chosen groups of college freshmen science programming interspersed either with anti-tobacco ads or with anti-marijuana ads, then gave them questionnaires designed to measure their attitudes and intentions regarding marijuana. "The group exposed to anti-marijuana [ads] shows significantly less negative attitudes [toward] marijuana…than the group exposed to anti-tobacco ads, while controlling for differences in preexisting attitudes," they report. "The same pattern of differences in the opposite than intended direction emerged from responses to questions about the intention to use marijuana."
While an exercise designed to measure "implicit attitudes" showed movement in the intended direction, the researchers say the practical significance of that measure is unclear, since it "can be sensitive to the associations a person has been exposed to in his/her environment…but this knowledge does not necessarily reflect personal endorsement." As for why teenagers might be more favorably inclined toward pot after watching the government's anti-pot ads, the authors note:
If the persuasive communication evokes disagreement with the content of the message, it provokes a recipient to generate counterarguments…A boomerang effect in response to persuasion is increased when the message is perceived as weak [or] inconsistent with prior knowledge, and when the source's credibility is suspect….Past anti-drug media campaigns in the U.S. have been criticized for exaggerated use of fear-based arguments and some factual inaccuracies, practices that some researchers warned might backfire by reinforcing attitudes opposite to [those] intended by the campaigns' creators.