Bloodstain pattern analysis using henna dye (Lawsia inermis)

Abstract

As a result of its viscous nature, blood stain patterns formed from blood splatter makes blood one of the most common pieces of evidence encountered. Bloodstain pattern analysis (BPA) is a branch of forensic science that examines the physical properties of blood and uses graphical pattern recognition to map out and evaluate bloodstains found at crime scenes and crime scene reconstruction. Crime scene reconstruction ensures a better understanding of events that unfolded at a scene. However, health and ethical issues in using real blood during reconstruction have led scientist to search for alternatives to mimic blood. An investigation using henna dye to mimic bloodstain by dropping from different heights (3 to 7 feet) was carried out in an outdoor crime scene simulation area. With the necessary steps involved in post scene processes diligently followed, it was observed that at 3 the formation of insignificant
satellites with small spines around each drop, at 4 feet minimal satellite stains and longer spines appeared, at 5 feet very small spines and minimal satellites were observed with an elongation on parent droplet, at 6 feet shows more distant longer satellites and at 7 feet tiny elongated droplets observed with satellites and had smaller droplet attached. It was concluded that when the height of dropping fake blood is increased, the distance of satellite stains emerging from the fake bloodstain also increases. Therefore the bloodstain pattern formed is dependent on the height of the blood spatter on a horizontal surface. Therefore henna could be used to for investigations of crime scenes and educational studies on bloodstain pattern analysis (BPA).