文件上有色指印非纹线特征的应用研究

为了充分地发掘模糊指印形态特征在司法实践中的可用性和实用性,我们利用文件上有色指印的阶段性痕迹--墨迹边缘状态、积墨形态分布“、空白”形态分布及其相互位置关系等非纹线特征,分析研究了不同捺印人以油墨为介质连续捺印的样本指印50组共200枚,结果发现使用非纹线特征能够准确地分辨出同一手指连续捺印的同组指印。本文还对应用指印非纹线特征的各项技术要点进行了讨论,并且列举了该方法用于鉴定实践的三个成功案例。指印非纹线特征的应用不仅改变了对模糊指印只能出“具不具备鉴定条件”的结论模式,而且使适合使用该方法的被检指印形成相对时间的难题得到解决。

The Application of Non-Ridge Attributes of Colored Fingerprints on Questioned Documents

Theoretically, only when sufficient attributes of ridge details are in agreement can identification of two fingerprints be reached. Examination of blurred fingerprints with no or insufficient ridge details usually ends with inconclusive results. In the study, the application potential of blurred fingerprints on questioned documents was explored, and non-ridge attributes of fingerprints-marginal and inner ink mark appearance, blankness patterns, and spatial relationships-were investigated. Specimens of 50 groups with 200 fingerprints pressed using inkpad were collected. It was shown that fingerprints left by consecutive pressing could be correctly identified by comparison of non-ridge attributes. Technical Points of the method were discussed and 3 cases were demonstrated. It is suggested that non-ridge attributes of fingerprints could be applied not only to solve identification problems of blurred fingerprints in some specific situations, but also to determine related timing of these fingerprints.