Types of Evidence Recovered form a Crime Scene
There are three different types of that can be recovered from a crime scene these being;
Biological Evidence
Biological evidence is evidence that comes from a living organism, this type of evidence can consist of fingerprints, hair strands, bodily fluids etc. Biological evidence can be tested and examined which will give results that can show to be a match or not a match to another individuals biological preferences. This type of evidence can be categorized as biological according to its physical image although this may be seen as difficult for blood samples, semen samples and saliva samples (liquid samples) as they may be identified as a biological fluid but in fact may just be a normal liquid located at the scene. Although if a bodily fluid is present at a crime scene the SOCO will be able to identify a lot about this piece of evidence when observing it, for example if blood is found at a crime scene and it is dry this can mean that the crime was committed well before the FAO attended the scene where as if the blood sample is not dry and still bright liquid this will prove that the crime has been committed recently so the suspect may not have got far.
Physical Evidence
Physical evidence is evidence that an individual can physically hold, depending on the crime that has been committed will depend on the type of physical evidence the SOCO will look for at a crime scene. Types of physical evidence are weapons e.g. knifes, gun other types are clothing, glass etc. Physical evidence is significant to find at a crime scene as this can build a bigger picture of what crime has occurred and can also lead to more evidence being found as it will give the SOCO's an insight of what needs to be looked for, for example if a knife has been found with blood on the SOCO's will then look for other blood samples around the scene. If a knife is found at a crime scene this may also hold key evidence and information as it has been handled physically which will mean the knife will be dusted for fingerprints and also examined for bodily fluids. Depending on the pieces of physical evidence found at the crime scene can depend on whether another similar piece needs to be found, for example physical evidence is able to fit like a jigsaw if the piece of physical evidence is found broken then the police will be able to find the match which may lead to finding a suspect. For example if a knife has been used within the crime but the handle has fell off the blade the police will need to find the exact handle that will fit the blade, if this if found in a suspects property there is key evidence to link them to the case.
Chemical Evidence
Chemical Evidence is any substance that is found at a crime scene which can either be suspected to be a drug or gunshot residue etc, it can also be presented in a solid, liquid or gas form. The physical appearance of the substance is taken into consideration by the forensic scientist so they are able to test it for a certain type of drug. If gun shot residue is found at a crime scene this will mean that the police know a gun was involved in the crime and will be looking for the weapon, they also may examine any clothes the suspect was wearing to see if gun shot residue is present on there clothing as when the gun was fired this will have been released due to an exothermic reaction occurring.