As an objective fact to prove a case in criminal proceedings, evidence must have three basic attributes: objectivity, relevance and legitimacy. Broadly speaking, defective evidence refers to one or several aspects of evidence that are defective in objectivity, relevance and legality, that is, evidence is either defective in content, defective in expression or illegal in collection procedures. In a narrow sense, defective evidence refers to evidence that is objective and relevant, but has defects in the elements of legitimacy.
Specifically, it only refers to the evidence that the procedure or method is illegal and the evidence that the subject is illegal. What I want to discuss here is limited to defective evidence in a narrow sense, that is, evidence with illegal characteristics and incomplete elements collected and provided by relevant judicial staff in violation of the authority and procedures prescribed by law or in any other illegal way.
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