Lying and truth-telling in children: from concept to action.

Although there has been extensive research on children's moral knowledge about lying and truth-telling and their actual lie- or truth-telling behaviors, research to examine the relation between these two is extremely rare. This study examined one hundred and twenty 7-, 9-, and 11-year-olds' moral understanding of lies and their actual lying behaviors in a politeness situation. Results revealed that as age increased, children increasingly evaluated others' lying in politeness situations less negatively and were more inclined to tell lies in such situations themselves. Contrary to previous findings, children's sociomoral knowledge about lying was significantly related to their actual behaviors, particularly when children's rationales underlying their moral judgments were consistent with their motives for actual lie- or truth-telling in the politeness situation.