Th effectiveness of soot removal techniques for the recovery of fingerprints on glass fire debris in petrol bomb cases

The increased use of petrol bombs as an act of vengeance in Malaysia has heightened awareness for the need of research relating physical evidence found at the crime scene to the perpetrator of the crime. A study was therefore carried out to assess the effectiveness of soot removal techniques on glass fire debris without affecting the fingerprints found on the evidence. Soot was removed using three methods which were brushing, 2 % NaOH solution and tape lifting. Depending on the visibility of prints recovered, prints which were visible after soot removal were lifted directly while prints that were not visible were subjected to enhancement. Glass microscope slides were used in laboratory experiment and subjected to control burn for the formation of soot. Soot was later removed following enhancement of the prints over time (within 1 day, within 2 days and after 2 days). While in simulated petrol bomb ground experiment, petrol bombs were hurled in glass bottles and the fragments were collected. Favorable results were obtained in varying degrees using each soot removal methods. In laboratory testing, brushing and 2 % NaOH solution revealed fingerprints that were visible after removal of excess soot and were lifted directly. As for tape lifting technique, some prints were visible and were successfully lifted while those that were not visible were subjected to super glue fuming for effective fingerprint identification. (author)