Presumptive testing can be a very useful tool in the early stages of an investigation. However, it can cause issues in some circumstances and may lead to some uncertainty over the origin of a sample. Evaluate the use of presumptive testing at crime scenes and consider both advantages and disadvantages of the techniques.

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Presumptive Testing of Body Fluids

Scenario

Having an indication of what the source of a particular body fluid is at a scene can provide useful information to an investigation. It can not only assist with the subsequent recovery strategy but also build a picture of the events that lead to that fluid being present. There are a variety of presumptive tests available that can indicate the presence of particular fluids.

These questions will explore your knowledge of presumptive testing and allow you to demonstrate your research skills. You should use in-text referencing where appropriate.

 

  1. A red stain has been found at a crime scene and the Crime Scene Investigator suspects it may be blood. What tests are commonly available at scenes to indicate to the CSI that the stain could be blood. Give a brief description of how these tests are carried out.

 

  1. Luminol is a chemiluminescence test that was first discovered in the 1930s. What is Luminol and how might it provide advantages over any other tests you mentioned in your answer to question 1?

 

  1. Presumptive testing can be a very useful tool in the early stages of an investigation. However, it can cause issues in some circumstances and may lead to some uncertainty over the origin of a sample. Evaluate the use of presumptive testing at crime scenes and consider both advantages and disadvantages of the techniques.