Abstract

The concealed information test (CIT) assesses the recognition of crime-relevant information, which is possible to conduct only when specific material evidence is seized. As an attempt to solve this problem, we examined whether the P300-based CIT using the suspect’s statement is a potentially valid method to classify an individual as guilty or innocent. Therefore, we compared the event-related potentials in four conditions to imitate various situations at the scene of crime investigation: false statement(n=16), confess(n=16), deny(n=16) and innocent(n=17). Results showed that the difference in P300 amplitude between probe and irrelevant was significant in the false statement, confess and deny conditions, but not in the innocent condition. Moreover, false statement in the false statement condition elicited larger P300 amplitude than irrelevant, but probe elicited larger P300 amplitude than false statement. These results suggest that the P300-based CIT is possible to detect the actual criminal behavior from false statements and assess the veracity of confessions.