A Theory Of The Demeanor Evidence

Demeanor refers to one's words and deeds.In the judicial context,it refers to the facial,verbal,and body expressions of the parties and witnesses in judicial activities.During investigations and trials,the observation and analysis of the outward demeanor of objects provides important guidance for investigators,prosecutors and trial judges to find the case facts,examine the credibility of evidence,and confirm or eliminate suspects.With the development of evidence laws and other related laws,modern judicature emphasizes the standardization of the rules of evidence and procedure.In practice,demeanor observation is considered as subjective judgment,difficult to quantify and evaluate objectively.It does not meet the objective requirements of modern evidence law.Therefore,its evidential effect has always been denied.However,the application of demeanor observation has never been completely abandoned in the field of judicial theory and practice.This paper is devoted to exploring the present situation,principle,dilemmas and the possibility of the application of demeanor evidence in today the judicature in the context of modern technologies.At present,the understanding of demeanor evidence is still limited to be "auxiliary" for judging the authenticity of verbal evidence in the trial stage.The development of science and technology is the starting point for contemporary judicature to re-understand demeanor evidence,and the discussion at the technical level shall include both its scientific connotation and technical denotation.Supported by the current behavioral science and psychology,demeanor evidence that can be observed and analyzed scientifically is the result of multi-modal analysis,such as eye-tracking detection,voice emotion analysis,cognitive EEG detection,physiological polygraph,facial expression recognition analysis,and limb behavior analysis.Because of the limitations of modern procedural rules,demeanor evidence should be defined as the conclusive opinion formed by professionals who use analytical instruments to collect and interpret the external physiological expression of the entire human body,which is directed by Autonomic Nervous System and not controlled subjectively.Demeanor evidence has been deeply rooted in judicial practice for thousands of years,first in the form of empirical observation of modal materials in ancient judicial practice,such as "Five Hearings to Decide a Lawsuit" in West Zhou Dynasty of Ancient China,and the magistrate in the justice system of Ancient Rome.Second,it took the form of lie detection techniques,which offered preliminary measurement of demeanor.At present,the global controversy over lie detection focuses on the legitimacy of technology and the evidential effect of its conclusion.The third form is the multi-modal quantitative demeanor evidence in the context of modern information technology,which is also the demeanor evidence discussed in this paper.The three forms of demeanor observation coexist with no contradiction,and play their respective roles in judicial practice.After the development of judicial practice from perceptual knowledge to rational analysis,and from subjective judgment to objective quantitative analysis,demeanor evidence exists merely nominally in judicial practice with its definition under dispute.There are three main dilemmas in the application of demeanor evidence at present.First,judicial practitioners lack trust in the evidential effect of demeanor evidence due to the traditional stereotype of "mental observation".Secondly,due to the lack of understanding of the scientific basis of demeanor evidence and the limitations imposed by traditional evidence rules,judicial practitioners affirm the ability of demeanor evidence to prove the facts of evidence while denying its ability to prove the facts of a case.Thirdly,there is controversy on whether the acquisition of demeanor evidence violates the free will of the observed person.Firstly,demeanor evidence can be used to evaluate the credibility of verbal evidence and demonstrate the concept of "fine judicature".Secondly,the application of demeanor evidence can construct a scientific and rational view of oral evidence.Thirdly,the use of demeanor evidence can facilitate the appearance of witnesses in court,enable the attainment of information on case facts transmitted in testimonies in a more objective,comprehensive and accurate manner,truly realize the positive value of witnesses' appearance in court,and promote the substantive development of court trials.Finally,the application of demeanor evidence is helpful for retrospective investigation and the realization of the true value of litigation.First,neurobiological experiments are carried out to construct the animal stress model of demeanor evidence and analyze the molecular biological function of biological demeanor evidence,in order to verify the scientific basis of multi-modal evidence observation.Secondly,behavioral psychological experiments are carried out to form a synthetic analysis of speech,physiology,eye movement,facial micro-expression,limb movement and so on in order to verify the whole occurrence of behaviors and their relationship with external stimuli.Finally,a model is established based on the experimental data to calculate the accuracy of the multi-modal evidence by Bayesian algorithm,which proves the authenticity,relevance and accuracy of demeanor evidence in the field of evidence law.Demeanor evidence covers a variety of demeanor observation models and analysis techniques,which can be generated in the pretrial and trial stage.Reflecting on the closed model of evidence categories in China in the pretrial and trial stage.The author suggests that demeanor evidence should be included in the current legal evidence hierarchy as expert opinions.Meanwhile,the argument focuses on the protection of human rights in the acquisition of demeanor evidence by establishing the basic principle of "voluntary confession",and attempting to establish the rules for the protection of rights such as freedom of will,personal freedom and the right to know in the acquisition of demeanor evidence.Rules of probative value for demeanor evidence shall combine both general and special rules,qualitative and quantitative rules,and mainly apply to negative evidence,with affirmative evidence as supplement.Moreover,different categories of evidence shall be treated differently.Relevance rules shall be used to analyze relevance not only in the traditional sense,but also in the application of demeanor evidence.The rules should be introduced to the relevance assessment of scientific and technological evidence and the right to know rules which quantify probative value.In this way,relevance rules are applied in the sense of probability theory,to briefly analyze the process by which the probative value of demeanor evidence is determined.First of all,the author analyzes the problems that may arise from the application of demeanor evidence,including wrongful judgments and aggravation of inequality between prosecution and defense.It then goes on to discuss the necessity of regulation on the premises and risks in the generation of demeanor evidence in order to avoid litigation risks.Finally,it explores the review and assessment for the application of demeanor evidence from the perspective of exclusionary rules of illegal evidence.