The aversion to lying

We experimentally investigate the effect of cheap talk in a bargaining game with one-sided asymmetric information. A seller has private information about her skill and is provided an opportunity to communicate this information to a buyer through a written message. Four different treatments are compared: one without communication, one with free-form communication, and two treatments with pre-specified communication in the form of promises of varying strength. Our results suggest that individuals have an aversion towards lying about private information and that the aversion to lying increases with the size of the lie and the strength of the promise. Freely formulated messages lead to the fewest lies and the most efficient outcomes.