Preservation and Collection of Evidence



Evidences within a crime scene could take on many forms. Therefore, you could easily move objects or touch any item without realizing that you are actually destroying a potential clue for a crime's solution. Crime scene investigators are aware of the standard procedures involved upon searching a crime scene in order to keep them intact for interpretation and analysis. Since each type of evidence offer its own individual value for the crime scene investigation, below are a list of evidence with some of the procedures done to preserve their original condition.

Fingerprint Evidence

Any type of prints, whether palm prints or bare footprints, are considered to be valid evidence of an individual's presence at a crime scene. There are a few basic materials you need to collect samples of fingerprints and yet it a very strong piece of evidence. Any items in a crime scene that are incapable of moving, like fingerprints, need to be processed at the crime scene using any type of powder such as gray, black, or black magnetic powder. Aside from collecting items, fingerprints are one of the top priority at a crime scene. 

Marks or Scars

Bodily marks or scars are common amongst crime involving any type of assault. When collecting them as evidence, crime scene investigators normally require a special type of camera that is capable of capturing such evidence for use later on in the analysis stage. If possible, take as many pictures as you can from many different angles. This will help not only in the analysis but in the consistency and validity of such marks and scars as evidence. If there are any visible impression produced from the bite marks, then you can probably work on creating a cast out of that. It could help in matching with the suspect's teeth after the lab results are revealed.

Documents

Indoor crime scenes produce several search opportunities for the crime investigators because you are not limited within the actual scene of the crime. You can also have access to other documents that could point to the identity of the suspect or motive behind the crime. For instance, questionable documents or handwriting samples can be used to trace the identity of a suspect by conducting matching tests. You can also use such documents to search for fingerprint patterns. Most crime scene investigating team have their own expert questioned documents examiner to handle this type of job.

Body Fluids or Stains

Blood or seminal fluids are important during crime scene investigation. It can be tested in the criminal laboratory to get DNA samples that will help identify the suspect. As opposed to other types of evidence that will only provide clues, this one is strong indicator of an individual who committed the crime. When it comes to collecting samples of dried blood or other fluid stains, you can follow the steps below:

•	If an object is stained by a given type of fluid, then you can bring that object for examination at the lab.

•	If the object cannot be transported, you can use a fingerprint tape. Place the tape against the part of the object stained with the fluid and lift it to get the stain. 

•	You can also use scraping devices to remove the stains from an object and secure them in a container or plastic bag. Make sure that the plastic bags you use are air dried to avoid diluting the dried fluid you acquired from the crime scene. 

Shoeprints and Other Impressions

Impressions and tracks produced by the suspect's shoes are a positive evidence that could help identify the suspect. Therefore, tire tracks or shoeprints are often what crime scene investigators look for at a crime scene. Tracks or impressions can offer many things to the investigation. First, it can point to an identity of a suspect. Second, it can also help you follow the tracks to indicate where the suspect is headed to, whether he is traveling on foot or riding a vehicle. 

