The paper presents basic approaches to object identification and probability access in forensic investigation. The author discusses the probability of expert examinations. Between the extreme borders of individual identification and determination of group membership, it is possible to narrow down the set of objects searched in some cases by calculating the probability level. The probabilistic point of view of the findings of the expert examination is expressible by word interpretation, often expressed also by numerical value. The notion of stochastic, ie the probability of narrowing of group membership, appears in criminological literature in the past. The author deals with the stochastic approach and the determination of the boundary for the high probability level.