Blood Evidence Essay

Blood is present at most crimes scenes involving any type of violence (Library). Blood presents investigators with further information to determine the sequence of events that may have taken place between the victim and the suspect. If there is any evidence collected from the scene, it should be properly packaged, labeled and sealed before it is sent to the lab for testing. In order for proper laboratory applications and court usage, there should be accurate labeling. Any item that has to be submitted to the laboratory should include the name or names of the suspects or victims, a description of the evidence of the package, the location the items were collected, and the investigator’s first and last name along with the date and time that the …show more content…

The first test is the Conventional Serological Test, which analyses proteins, antigens and enzymes present in blood samples. The elements tested under the Conventional Serological Test are exposed to degradation and requires large samples to obtain best results. The second test is the Restriction Fragment Length Polymorphism, which analyses the presence of certain DNA sequences in the white blood cells. Like proteins and enzymes, DNA does not degrade and, therefore, this procedure is less likely to be affected by degradation. The third type of test is the Polymerase Chain Reaction Test, which assists in the analysis of DNA series that have been copied several times to a measurable …show more content…

These tests are specifically for identifying the presence of human saliva in samples submitted into the laboratory. The Phadebas test comes to great use when trying to identify the presence of the enzyme alpha-amylase, which is typically present in human saliva. As contrasted to the Phadebas test, the RSID test checks for the molecule of alpha-amylase in the sample rather than the activity of the enzyme, as it is the case with the Phadebas test. Apart from these tests a DNA test can also be conducted on the sample to identify the source of the sample and in such circumstances the suspects or the victim’s saliva should also be available for