ISSN : 2093-3843
Witnesses will be exposed to a variety of misinformation after the witnessing of the event and state at the scene of the investigation after the delay period. This study was conducted to promote correct recall reporting without being affected by factors that against correct recall. Self-Administered Interview(SAI) is known to obtain eyewitness accounts quickly and accurately. Therefore, we performed a SAI to see if it reported more information than the control group that did not perform the SAI. Also, it also performed that correct information was maintained without being affected by misinformation and delay. Eighty-eight participants were asked to perform SAI or game after showing a video of mock crime. Misinformation was presented in the first or second session to see if it affected recall. An analysis of responses from the final test conducted in the second session by participants showed that groups that conducted SAI after a four-week delay reported more correct information than control groups, while there was no difference between incorrect- and confabulation information. In particular, the timing of presenting misinformation did not affect the amount of recall. This suggests that conducting the SAI immediately after witnessing the event protects correct information even after four weeks. Finally, the significance and limitations of this study, and subsequent studies were discussed.
In P300-based concealed information test (P300 CIT), it evaluates whether the P300 amplitude for the probe is significantly greater than that of the irrelevant to determine if the suspect is telling a lie. An independent sample t-test or a bootstrap method can be used as a statistical test to make that decision. Rosenfeld et al. (2004) used the bootstrap method, claiming that “t tests on single sweeps are too insensitive to use to compare mean probe and irrelevant P300s within individuals” and their method has been accepted to date. The purpose of the study is to evaluate whether the power of t-test is lower than that of the bootstrap method in the P300 CIT. The Monte Carlo study was conducted by using EEG collected from 39 participants. The results showed that the type I error rates of the t-test and the percentile bootstrap method were similar and the power of the percentile bootstrap method was slightly higher than that of the t-test. The type I error rates of the t-test and the percentile bootstrap method were slightly lower than the significance level and the powers of the two tests were also slightly lower than that of the theoretical t-test. On the other hand, the type I error rate and power of the standard error Bootstrap method were the same as those of the theoretical t-test and its power was .012 ~ .081 higher than that of t-test depending on experimental conditions.
Lee, Khogali, Despodova, and Penrod (2019) demonstrated that American participants whose races are different from a defendant and a victim rendered more punitive judgments against the defendant in a same-race crime (e.g., White observer-Black defendant-Black victim) compared to a cross-race crime (e.g., White observer-Black defendant-Hispanic victim). The aim of the current study was to test the replicability of their findings in a different country-South Korea. Study 1a failed to replicate the race-combination effect in South Korea with three new moderators-case strength, defendant’s use of violence, and race salience. Study 1b was conducted with the same design of Study 1a in the United States to examine whether the failure of the replication in Study 1a was due to cultural differences between South Korea and the United States. However, Study 1b also failed to replicate the race-combination effect. Study 2 conducted a meta-analytic review of the data from Lee et al.’s (2019) study, along with the data from Study 1a and 1b and revealed that the race-salience manipulation in Study 1a and 1b might have caused the null results. We conclude that when people’ races are different from both a defendant and a victim, they are likely to render more punitive judgments against the defendant in a same-race crime than a cross-race crime. However, the race-combination effect is only sustained when race-relevant issues are not salient in the crime.
Judgment and decision-making studies have shown that people are easily influenced and biased by information irrelevant to the object of judgment. There is a great deal of research that indicates that bias exists in the legal judgment scene. One of them is a bias induced by defendants’ character evidence. This study examined whether cognitive activities such as discussion, counterfactual thinking, and peer assessment could reduce the bias induced by the character evidece. In Experiment 1, 121 college students were asked to give the percentage they believed the defendant to be guilty. There was no cognitive activity for the control group. There were three different cognitive activities for the experimental group: discussion, counterfactual thinking and discussion, and counterfactual thinking and peer assessment. Results showed reduction in bias for all the experimental groups, and there was no difference between them. In Experiment 2, there were 125 participants from general population for the same procedure as in Experiment 1. Results showed reduction in bias only for the counterfactual thinking and discussion group. In general discussion, we speculated the implication of the results and the reason for the difference between the two experiments.
Traditional deception detection methods had examined the difference of one’s autonomic physiological responses through asking crime-related and crime-unrelated questions. There has been a continuing controversy regarding the accuracy and validity of the test, and thus, many researchers were motivated to explore and develop alternative efficient methods of detection in which one of them is known as P300-based Complex Trial Protocol (CTP). The P300-based CTP detects deception through comparing the P300 amplitudes between probe and irrelevant stimuli and is known as a counterstrategy of countermeasures. However, many previous studies have used countermeasures created from Rosenfeld et al.’s work (2008).The present study initially conducted a survey asking open-ended questions about the countermeasure use to acquire participant-oriented countermeasures for the main experiment. Then, the study aimed to evaluate whether the CTP can accurately detect deception even in the use of survey-based countermeasures. We firstly selected a set of participant-oriented countermeasures through survey questions. Then, a total of 50 participants were divided into three groups (innocent, guilty, and countermeasures) and performed the CTP. Those assigned to the countermeasures group covertly performed mental countermeasures during the CTP. The results of P300 amplitude analysis revealed that the guilty group’s P300 amplitude of probe stimuli was significantly larger than that of irrelevant stimuli. Countermeasures group also had a significantly larger P300 amplitude for probe stimuli compared to irrelevant stimuli, even in the use of countermeasures. The results of bootstrapped amplitude difference (BAD) showed a detection accuracy rate of 81.25%, 82.35%, 82.35% for the innocent, guilty, and countermeasures groups, respectively. These findings demonstrate that the CTP can obtain a high detection rate in participant-oriented countermeasures and suggest the potential use of the CTP in the