"We found that consumer's willingness to lie is related to not only a desire to protect their public selves, or the impressions they convey to others, but also [their] private selves, or their sense of self worth," explain Jennifer J. Argo (University of Alberta), Katherine White (University of Calgary), and Darren W. Dahl (University of British Columbia).
The first study to use social comparison theory to explain why and when we lie, the researchers argue that our willingness to lie is directly related to perceived threats to our self-esteem and self-image. People feel threatened by the possibility of being suckers and lie more readily when they overpaid for an item. However, people are less likely to lie if they know that a better deal is attainable, say, with a short-term gym membership.
"When public self image is threatened, individuals are often motivated to engage in impression management tactics such as lying," explain the authors.
"The results of the study demonstrate that individuals appear to be willing to lie to someone they know and with whom they have a relationship. Worse yet, the reasons they are willing to lie are self-focused in nature - they are concerned with protecting their self-image and self-worth."
Jennifer J. Argo, Katherine White, and Darren W. Dahl. "Social Comparison Theory and Deception in the Interpersonal Exchange of Consumption Information" Journal of Consumer Research. June 2006.