In recent years, the amount of digitally captured traces at crime scenes increased rapidly. There are various
kinds of such traces, like pick marks on locks, latent fingerprints on various surfaces as well as different micro
traces. Those traces are different from each other not only in kind but also in which information they provide.
Every kind of trace has its own properties (e.g., minutiae for fingerprints, or raking traces for locks) but there
are also large amounts of metadata which all traces have in common like location, time and other additional
information in relation to crime scenes. For selected types of crime scene traces, type-specific databases already
exist, such as the ViCLAS for sexual offences, the IBIS for ballistic forensics or the AFIS for fingerprints. These
existing forensic databases strongly differ in the trace description models.
For forensic experts it would be beneficial to work with only one database capable of handling all possible
forensic traces acquired at a crime scene. This is especially the case when different kinds of traces are interrelated
(e.g., fingerprints and ballistic marks on a bullet casing). Unfortunately, current research on interrelated
traces as well as general forensic data models and structures is not mature enough to build such an encompassing
forensic database. Nevertheless, recent advances in the field of contact-less scanning make it possible to acquire
different kinds of traces with the same device. Therefore the data of these traces is structured similarly what
simplifies the design of a general forensic data model for different kinds of traces.
In this paper we introduce a first common description model for different forensic trace types. Furthermore,
we apply for selected trace types from the well established database schema development process the phases of
transferring expert knowledge in the corresponding forensic fields into an extendible, database-driven, generalised
forensic description model. The trace types considered here are fingerprint traces, traces at locks, micro traces
and ballistic traces. Based on these basic trace types, also combined traces (multiple or overlapped fingerprints,
fingerprints on bullet casings, etc) and partial traces are considered.
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