ABSTRACT
There are several reasons why the detection of organic constituents of firearm discharge residue (FDR) was worthy of investigation. The detection of organics is much faster, particularly for multisuspect cases involving a large number of samples, and it was hoped that the time problem could be partly solved by screening for organics prior to inorganic examination, enabling preliminary results to be available for the police investigation. The majority of terrorist shooting incidents in Northern Ireland involve the use of single based propellants, and as the main thrust to date in organic FDR analysis had been based on the detection of Nitroglycerine (NG) from double based propellants, using techniques such as gas chromatography/thermal energy analyser (GC/TEA) and high-performance liquid chromatography/pendant mercury drop electrode (HPLC/PMDE). In the Northern Ireland Forensic Science Laboratory (NIFSL) two separate sections dealt with the detection of firearm and explosive residue. The chapter describes the development of a clothing sampling method, common to both explosive and firearm residue.
