This study examined maltreated and non-maltreated children’s (N = 183) emerging understanding of ‘‘truth’’ and ‘‘lie,’’ terms about which they are quizzed to qualify as competent to testify. Four- to six-year-old children were asked to accept or reject true and false (T/F) statements, label T/F statements as the ‘‘truth’’ or ‘‘a lie,’’ label T/F statements as ‘‘good’’ or ‘‘bad,’’ and label ‘‘truth’’ and ‘‘lie’’ as ‘‘good’’ or ‘‘bad.’’ The youngest children were at ceiling in accepting/rejecting T/F statements. The labeling tasks revealed improvement with age and children performed similarly across the tasks. Most children were better able to evaluate ‘‘truth’’ than ‘‘lie.’’ Maltreated children exhibited somewhat different response patterns, suggesting greater sensitivity to the immorality of lying.