The idea that no two people have the same fingerprint was introduced in 1880. Fingerprinting started to be used shortly after. Fingerprints were classified into three groups. They were arches, loops, and whorls. Later, fingerprints were classified into five groups, which are: tented arches, arches, whorls, and loops were divided in two groups. Investigators use these five groups today. There are three different types of fingerprints impressions. They are latent, visible, and the molded print. The print most often found by investigators is the latent print, which is invisible to the eye. Latent prints are formed by moisture that is on your hands. Even if you dry your hands off with a towel you will leave your fingerprint on any surface that you touch. The best way to develop a latent print is to dust over it with gray or black fingerprint powder. The second type of fingerprint is the most legible. It is made from fingers stained by blood or ink and is rarely found at a crime scene. The third type of print is the molded. It is an impression made on a soft surface and is also rarely found at a crime scene. If a print is left on a hard, protected surface and left untouched, it is almost permanent.
When a dead body is found, it is very important to determine the cause of death. There are three questions that need to be asked when determining the cause of death. They are: Who is the person? How long has the person been dead? What killed that person? Finding the cause of death can tell investigators whether or not foul play is involved. It is often the question of what killed that person that helps investigators solve the most challenging cases. A complete and accurate autopsy is very important when trying to determine the cause of death. If the pathologist can't determine the cause of death, he or she must take samples of body tissue and fluids for analysis. Pathologists can usually determine the cause after analysis.
