Layperson Deception

Research has consistently shown that people are not accomplished at judging truth and deception, generally performing at no better than chance level (Meissner & Kassin, 2002). Police and layperson accuracy and confidence are exceedingly important since many criminal offenders engage in high levels of manipulation and deception (Porter et al., 2000). Generally in psychology research we are asking participants to respond to a question then to rate the confidence of their response. In legal psychology research, many times comparisons are drawn between police and layperson samples. A recent overview of literature suggests that most police samples as a whole rate their confidence as high when they actually have similar or lower accuracy then layperson

In a study by Brigham and Spier (1992), 79% of the child protection workers and 76% of the police officers thought that they could for the most part tell when a child lied. This is a problem since confidence is rarely significantly correlated with accuracy, most likely due to relying heavily on nonverbal cues that are misleading (Nysse-Carris et al., 2011). As a group, these studies suggest that police report their confidence as high during certain tasks such as deception detection and are either just as accurate or less accurate than the public. Consistently, research has shown that people are not skilled at judging truth and deception, usually performing at no better than chance level, that training programs produce only limited and unreliable improvements in ones performance, and that police compared to laypeople frequently perform no better (Kassin et al., 2005). A study on layperson confidence and accuracy in deception detection has suggested that overall, judgments of confessions as either true or false were only correct 48.9% of the time, 50% being chance level. Participants in this study were to some extent confident in their judgments even though they frequently had low accuracy

Remarkably, no empirical meta-analysis studies to our knowledge have directly investigated the relationship between confidence and accuracy in layperson and police samples with a focus on deception detection. This study is needed to further examine this relationship since pervious research has shown that high confidence often results in making abrupt decisions on the basis of limited information (Vrij & Mann, 2001). High confidence has been shown to have negative effects in various ways. It may make the individual less motivated to collect more information on the topic since their high confidence may cause them feel as though they know everything about it already (Vrij & Mann, 2001). In addition, too much confidence may have consequences when information is presented in the courtroom. Research has shown that how confident an individual is or seems often has an influence on the jurors (Vrij & Mann, 2001). If police show high confidence when they are in fact not accurate it can be damaging to the outcome of the case. Lastly this kind of research is important due to the relevance that police procedures like detection of deceit has to police work. This makes it necessary to analyze to what magnitude police officers are able to differentiate between truthful and deceptive