How The Study On Development Of Forensic Blood Substitute: Focusing On Blood Pattern Analysis

Bloodstain pattern analysis, one of the areas of forensic science, is performed to analyze the physicalc haracteristics of bloodstains, including their size, shape, and distribution, to reconstruct a crime scene. A bloodstain pattern analyst should obtain through experiments and education the capabilities to both understand the generation mechanisms of bloodstains and identify the characteristics of the bloodstains. Experiments and education about bloodstain pattern analysis are carried out by using human blood taken from subjects, animal blood (porcine or bovine) supplied from butcheries, and blood substitute products developed in other countries. However, these kinds of blood have many limitations in their application due to various problems. The blood substitute developed in the present study is more similar to human blood than other blood substitute products developed in other countries with regard to the physical properties, including viscosity, viscoelasticity, and surface tension, as well as the drip bloodstain patterns depending on the surface and coordinate characteristics of drip stains impact angle. Bloodstain pattern analysis, one of the areas of forensic science, is carried out to analyze the physical characteristics of bloodstains, including their size, shape, and distribution, to reconstruct a crime scene. Bloodstain pattern analysis enables one to not only reconstruct the crime scene of a bloody murder but also determine the authenticity of a suspect's statement and assume a suspect depending on the case. A bloodstain pattern analyst should obtain through education the capabilities to understand the generation mechanisms of bloodstains and to identify the characteristics of the bloodstains. A bloodstain pattern analyst should find out, from an experiment based on the identified characteristics, the assumption that can best explain the crime scene among the many assumptions that have been introduced to identify the causes of the targetb bloodstain or the bloodstain pattern. Ultimately, the bloodstain pattern analyst should be able to secure the probative power of the evidence in court by acquiring scientific reliability of the evidence through the reconstruction of the scene. Experiments and education about bloodstain pattern analysis are carried out by using the human blood taken from subjects, animal blood (porcine or bovine) supplied from butcheries, and blood substitute products developed in other countries. The problems of human blood include the objection that the subjects have against blood sampling, the possibility of offensive smell and decomposition, the danger of biological infection, the difficulty of massive blood supply when needed, and the difficulties involved in the control of experimental conditions due to the change of the physical properties caused by the use of an anticoagulant. Animal blood also has problems such as the possibility of bad smell and decomposition, the danger of biological infection, the difficulty of supply due to the low marketability, and difficulties involved in the control of experimental conditions due to the physical properties that are different from those of the human blood. In addition, the blood substitute products developed in other countries have problems such as the economic burden due to their high price, incomplete validation of the physical properties through experimental comparison with the human blood, and difficulties of preparation and sale due to the separate functionalities of the pattern reproduction and luminol reaction.