Post firing visualisation of fingerprints on spent cartridge cases

A considerable range of techniques is available to visualise latent fingerprints on smooth surfaces. Published methods and those developed or modified in the authors' laboratory have been evaluated for spent cartridge cases. The most suitable were found to be vacuum cyanoacrylate (with fluorescent staining) and selenious acid treatments. Both were used to investigate the post firing recovery of finger-marks on spent cartridge cases from the ammunition and weapon systems encountered in terrorist casework in Northern Ireland. Only certain revolvers and the SLR rifle yielded identifiable ridge detail. These results are borne out by casework experience.