A recent experimental study of cai and wang [cai, h., wang, j., 2006. Overcommunication in strategic information transmission games. Games econ. Behav. 95, 384–394] on strategic information transmission reveals that subjects tend to transmit more information than predicted by the standard equilibrium analysis. To evidence that this overcommunication phenomenon can be explained in terms of a tension between normative social behavior and incentives for lying, we show in a simple sender–receiver game that subjects incurring in costs to punish liars tell the truth more often than predicted by the logit agent quantal response equilibria whereas subjects that do not punish liars after receiving a deceptive message play, on the aggregate, equilibrium strategies. Thus, we can partition the subject pool into two groups, one group of subjects with preferences for truth-telling and one taking into account only material incentives.