刑事错案形成的心理原因

刑事错案的成因包括直接原因、环境原因和心理原因,其中心理原因(主要表现为包括"遂道视野"、"证实偏差"等在内的各种心理偏差)对错案的形成有更根本的影响。绝大多数直接原因,如刑讯逼供、隐瞒有利于犯罪嫌疑人、被告人的证据、忽视辩护律师的合理意见等等,都是各种心理偏差的外在表现。而绝大多数环境原因,如不合理的考核方式、司法经费不足等等,之所以会导致错案,主要是因为它们强化了这些心理偏差。根据这些心理偏差对错案形成的可能影响,可以在心理学层面总结出刑事错案的形成过程及规律,而我国近年来纠正的22起刑事错案可以为此提供验证。我国有必要完善当前的刑事司法体制,以减少这些心理偏差对办案人员的影响,进而更有效地防止错案的发生。

Psychological Causes of Wrongful Convictions

The causes of wrongful convictions include direct causes, external causes and psychological causes. The psychological causes, including tunnel vision, confirmation bias, belief perseverance, reiteration effect, hindsight bias, outcome bias, noble cause corruption, emotional attachment, motivational bias and goal pursuit, play a decisive role in producing wrongful convictions. Most of the direct causes, such as extorting confession by torture, concealing exculpatory evidence, and not accepting argument of counsel, are just the manifestations of these biases in criminal justice. The reason why most of the external causes, such as the unreasonable performance measurement system, the pressure on police to solve high-profile cases quickly, lack of funds, and short of hands, contribute to wrongful convictions is that they reinforce the influence of these biases on the actors of the criminal justice. The process of wrongful conviction can be conceived on the basis of the potential influence of these biases. Put simply, the investigator misclassifies an innocent man as the criminal even the evidence against him is very weak, then he focuses too quickly or exclusively on this suspect, selects and filters the evidence that build a case for conviction, interprets the exculpatory evidence as either irrelevant or supportive of guilt, while ignoring or suppressing evidence that points away from guilt. The twenty two Chinese wrongful convictions corrected recently could be used to illustrate the way in which these biases affect the thinking and actions of police, prosecutors and judges. To minimize the influence of these biases on police, prosecutors and judges, so as to help the criminal justice system perform more accurately and reliably, the actors of the system should be educated and trained about the consequences, nature and effects of these biases. A variety of reasonable management and supervision practices should be adopted in police and prosecution institutions, transparency at all stages of the criminal process should be increased, and rights of defense should be better protected.