Forensic Science Progress

Thermal analysis methods have been introduced into forensic sciences only in recent times. Though thermoanalytical instruments have been available commercially for some decades it was not until the beginning of the seventies that forensic scientists became interested in them. At that time some state forensic science laboratories in the Federal Republic of Germany made use of differential thermal analysis for forensic soil investigations. The forensic science section of the city police of ZUrich, Switzerland, applied an instrument (differential thermal analysis and thermogravimetry) for various purposes. Investigations of fibers by means of differential scanning calorimetry were reported by the Centre of Forensic Sciences at Toronto, Canada, and on the characterization of candle-waxes by differential thermal analysis by the Metropolitan Police Forensic Science Laboratory, London, England. Later on some other insti­ tutions like the Bundeskriminalamt at Wiesbaden, Germany, or the Home Office Central Research Establishment at Aldermaston, England, purchased instruments for one or more of the following thermal analysis methods: differential thermal analysis or differential scanning calorimetry, thermogravimetry, and thermomechanical analysis. . But even now thermoanalytical instruments are not widespread in forensic science institutes and knowledge of their forensic potential seems to be limited. In the following chapters we will give a survey of the most important thermal analysis methods mentioned above, and on current forensic applications and/or fields of actual research efforts.

Contents/Information: 'Thermal Analysis Methods in Forensic Science' by G. Hellmiss: This contribution first explains the basics of the measuring process and the type of information obtained by the major TA methods, i. e. differential thermal analysis (DTA)/differential scanning calorimetry (DSC), thermogravimetry (TG), thermomechanical analysis (TMA). The next subject covers forensic science applications of TA. 'Optical Methods in the Examination of Questioned Documents' by J. Mathyer: Optical methods of examination include observations made by the naked eye, and microscopic examination with illumination in the visible or invisible range of the spectrum. 'Forensic Hair Investigation' by S. Seta, H. Sato and B. Miyake: The ultimate purpose of forensic hair comparison is to state whether a crime scene hair is of victim origin or of suspect origin. A combination of morphological and analytical data of hair samples, including hair protein and hair root and isoenzyme analysis leads to the enhancement of identification probability.