"Yes, I have sometimes stolen bikes": blindness for norm-violating behaviors and implications for suspect interrogations

Abstract

Across two experiments, we studied a phenomenon akin to choice blindness in the context of participants' accounts of their own history of norm-violating behaviors. In Experiment 1, N = 67 participants filled in an 18-item questionnaire about their history of norm-violating behaviors (QHNVB). Subsequently, they were questioned about four of their answers, two of which had covertly been manipulated by the experimenter. Of the 134 manipulations, 20 (14.9%) remained undetected concurrently and 13 were accepted in retrospect (9.7%). In Experiment 2 (N = 37), we inserted a one-week interval between questionnaire and interview. Twenty-seven (36.5%) of the 74 manipulations remained undetected concurrently and three were accepted in retrospect (8.1%). Data obtained in a four-week follow-up indicated that our manipulations may have long-term effects on participants' perception of their own history of norm-violating behaviors. Implications for the occurrence of false confessions during the course of an interrogation are discussed.