The verifiability approach: Countermeasures facilitate its ability to discriminate between truths and lies

According to the verifiability approach, liars tend to provide details that cannot be checked by the investigator and awareness of this increases the investigator's ability to detect lies. In the present experiment, we replicated previous findings in a more realistic paradigm and examined the vulnerability of the verifiability approach to countermeasures. For this purpose, we collected written statements from 44 mock criminals (liars) and 43 innocents (truth tellers), whereas half of them were told before writing the statements that the verifiability of their statements will be checked. Results showed that 'informing' encouraged truth tellers but not liars to provide more verifiable details and increased the ability to detect lies. These findings suggest that verifiability approach is less vulnerable to countermeasures than other lie detection tools. On the contrary, in the current experiment, notifying interviewees about the mechanism of the approach benefited lie detection.