随着司法鉴定专家以似然比方式表述证据性的依据,物证的司法鉴定证据力都逐渐倾向于用数学概率逻辑规则呈现。笔者通过查阅似然比在DNA检验、声像检验、笔迹检验等物证学中的应用和研究成果,通过对54式手枪、79式微型冲锋枪和85式微型冲锋枪射击利用似然比进行区五一式7.62mm手枪弹的弹头顶部碰面痕和弧形部磕碰痕迹观察、分析、统计,尝试运用贝叶斯原理达到区分枪种的目的。 As forensic experts express their evidence based on the likelihood ratio, the evidence of forensic evidence gradually tends to be presented by mathematical rules of probability and logic. Through reviewing the application and research results of the likelihood ratios in the evidence-based testing such as DNA test, audio-visual test and handwriting test, the author uses the likelihood ratios of 54-type pistol, 79-type mini submachine gun and 85- 7.62mm pistol bullet hit the top of the bullet hit the surface marks and traces of the arc collision observation, analysis, statistics, try to use Bayesian principle to distinguish the purpose of gun species.