Gavan J. Fitzsimons, Joseph C. Nunes, and Patti Williams in the Journal of Consumer Research (via EurekAlert!):
This research examines the impact of asking intention questions about “vice behaviors,” or behaviors about which respondents simultaneously hold both negative explicit and positive implicit attitudes. Asking questions about the likelihood of engaging in behaviors for which respondents maintain conflicting attitude structures appears to give respondents a “license to sin,” resulting in increased rates of behavior versus those of a control group not asked intention questions. However, when provided with defensive tools that highlight the negative explicit component of their attitudes toward the behaviors, respondents are able to dampen the increase in behavior caused by the act of prediction.