Problems of Forensic Sciences 2001 Vol. 47 (XLVII) 73-79
DESIGN OF A GLASS CASEWORK DATABASE INHERITING QUALITY ASSURANCE ASPECTS
Stefan BECKER1, Wolfgang BECKER2, Natalie FRITZ1, Detlef HIRSCHFELDER3, Klaus HOLZ4, Thomas KRIEGHOF5, 1, Mathias WEISE6
1Bundeskriminalamt, Forensic Science Institute, Wiesbaden, Germany
2Hessisches Landeskriminalamt, Wiesbaden, Germany
3Landeskriminalamt Saxony-Anhalt, Magdeburg, Germany
4Landeskriminalamt Schleswig-Holstein, Kiel, Germany
5Landeskriminalamt Saxony, Dresden, Germany
6Landeskriminalamt Baden-Württemberg, Stuttgart, Germany
Streszczenie
Based on the results of a proficiency test carried by 11 German federal state labs and one Swiss crime lab using different measurement protocols and equipment a project group was founded in 1999 aimed at working on the harmonisation of refractive index measurements. This group outlined minimum criteria for case working (“eleven laws” of refractive index measurement), taking into account existing documents like ASTM E 1967-98. In co-operation with the glass manufacturer SCHOTT a glass standard with controlled refractive index ±7 x 10–6 was obtained. This BKA-K5 standard was distributedto all German forensic state laboratories. This glass should be used as an external standard in order to ensure quality control charts. A database has been designed for scene of crime and suspect glass material. The database will include information on: refractive index, standard deviation, number of measurements, annealing, origin, colour, thickness, glass type, type of crime, date of measurement. The aim of this centralised database is to enhance the evidential value of a given case regarding the frequency of occurrence and further relevant questions. Statistical calculations (t-test) and grouping algorithms are also integrated into this software.
Słowa kluczowe
Database; External standard; Forensic glass interpretation; Refractive index; Quality assurance.