Abstract:  In China’s civil litigation, self-commissioned appraisal opinions are widely used as evidence. However, the theoretical community has not reached a consensus on the categorization of their evidence type, and there are contradictions in practice between strict proof and ambiguous legality, as well as conflicts between strong probative force and weak review rules. Re-examining from a normative perspective reveals that they do not fully meet the normative requirements of statutory expert opinions under China’s Civil Procedure Law, nor do they fall under the category of illegal evidence subject to exclusion. Considering the essential factors that contribute to the probative effectiveness of self-commissioned appraisal opinions, this paper argues that they should be classified as defective appraisal opinions and proposes the construction of a corresponding rule system for the review and determination of defective appraisal opinion. At the pre-trial conference stage, the commissioning party should fulfill the obligation of evidence disclosure by proactively disclosing the self-commissioned appraisal opinions and appraisal materials. At the level of evidence admissibility, the non-commissioning party has the right to raise evidentiary objections against substantive factors affecting the admissibility of self-commissioned appraisal opinions, and judges should deny their admissibility when reasonable doubts arise. At the level of probative force, since the defects in the neutral procedural value of self-commissioned appraisal opinions cannot be rectified, they should be categorized as evidence requiring corroboration. Although they cannot independently establish case facts, their probative force can be enhanced through other corroborative evidence.

Key words: self-commissioned appraisal opinion, scientific evidence, defective evidence, evidence defense, the corroboration rule

摘要： 在我国民事诉讼中，自行委托鉴定意见作为证据被广泛应用。然而，理论界对自行委托鉴定意见的证据种类归属莫衷一是，实践中也存在着严格证明与合法性模糊、强证明力与弱审查规则的矛盾冲突。从规范视角再度审视，可以发现自行委托鉴定意见并不完全满足我国《民事诉讼法》中法定鉴定意见的规范要件，亦不属于非法证据排除的情形。结合自行委托鉴定意见发挥证明效力的本质性因素，主张其应系瑕疵鉴定意见，并应构建相应的瑕疵鉴定意见审查判断规则体系。在庭前会议阶段，委托方当事人应履行证据开示义务，将自行委托鉴定意见及鉴定材料主动进行开示；在证据能力层面，非委托方当事人有权针对影响自行委托鉴定意见证据能力的实质因素提出证据抗辩，法官在产生合理怀疑时应当否定其证据能力；在证明力层面，基于自行委托鉴定意见在中立程序价值方面的瑕疵无法补正，因此其应被列为需要补强的证据类型，虽无法单独认定案件事实，但可借助其他补强证据来增强其证明力。

关键词: 自行委托鉴定意见, 科学证据, 瑕疵证据, 证据抗辩, 补强规则