The Influence Of Cognitive Bias On Expert Opinions And Its Countermeasures

Cognitive bias is a wrong way of thinking in the process of people's understanding and dealing with various information.Its existence is universal,it can be foreseen,but it is difficult to avoid.The forensic science should be scientific,objective and reliable.The identifier is the third person who has no interest in the case.The identifier's opinion made should be objective and fair,and should not be affected by factors that unrelated to the identification itself.However,in recent years,criminal errors caused by cognitive factors have occurred frequently in the identification,including some influential cases.With the in-depth study of cognitive problems in forensic identification by forensic science experts,The existence of cognitive bias in forensic science and the severity of its impact on forensic science are also emerging.the vast majority of current assessments in the field of identification are based on the subjective judgment of the identifier,and thus inevitably cause cognitive biases,Including fingerprint identification that is considered to be very reliable.The influence of various subjective and objective factors in the identification is likely to cause cognitive biases in the appraisers,which in turn leads to identification errors.In response to this problem,This paper proposes measures to apply the likelihood ratio method system and institutional norms in forensic science to solve the cognitive bias of the appraiser.The full text consists of the introduction,the body of the four parts and the conclusion.The introduction part mainly explains the problems studied in this paper,the current research status at home and abroad,and the significance of the research.Identification opinions are often considered to be objective and reliable,Due to the psychological factors of the person and the related information of the case,the identification opinions are influenced by the subjective opinions and even have errors..In recent years,many forensic science experts and psychologists in abroad have gradually strengthened their research on this issue,But domestic research on this issue is relatively rare.Therefore,by analyzing cognitive biases,it is proposed how to avoid and reduce the cognitive bias of the identifier in the identification,and thus improve the scientific reliability of the identification.The first part mainly introduces the concept and influencing factors of cognitive bias and their types.The influencing factors affecting cognitive bias include sociological factors and psychological factors.The types of cognitive bias mainly include confirmation bias,expectation bias and anchoring.The second part mainly analyzes the influencing factors of cognitive bias in forensic identification and the common forms of bias.Firstly,analyze the influencing factors of cognitive bias,It mainly includes seven aspects of case evidence,reference materials,case information,base ratio expectations,organizational factors,training and motivation,and cognitive architecture.Second is the type of cognitive bias commonly found in analysis and identification,including confirmation bias,expectation bias and contextual bias.The third part discusses the respective principles of fingerprint identification,handwriting identification and DNA identification,and then,compares and analyzes the causes of bias,the possible cognitive biases,and proposes the advantages of DNA identification mode in avoiding cognitive bias.The fourth part mainly introduces the methods and measures to reduce the cognitive bias of the identifier.Firstly,it expounds the meaning of the likelihood ratio method,and it's advantage of applied to forensic science in dealing with cognitive bias.Secondly,it discusses the measures that help to reduce the cognitive bias of the identifier in terms of institutional norms.The concluding remarks describe the role of likelihood ratio methods and institutional norms in reducing the cognitive bias of the identifier,and the value of implementing these measures of forensic science,pointing out the shortcomings of these measures,and expectations for more viable measures for the future.