Physical Evidence

Physical Evidence…

Physical evidence consists of any physical object that is found within any given crime scene. This evidence category consists of evidence such as, clothing, weapons, bullet casings, footwear marks etc. Any surveillance videos, handwritten documents or statements can be seen as physical evidence. This evidence can all be collected by a SOCO however it can also be obtained by a police officer or Lawyer in the case of video or photographic evidence. This evidence should be photographed before collection using a scale ensuring the measurements are captured within the image. This is to ensure that a documentation is kept of the evidence, this photograph should also be logged into the chain of custody along with the actual evidence. Depending upon the evidence will depend upon the bagging of the evidence. If it is a sharp object for example a knife, the object will be placed within a plastic container ensuring to injuries occur when transporting and moving the evidence around. If there is biological evidence upon the object such as blood, a sample should be taken using a swab and this should also be placed into the chain of custody stating where the substance was found. If clothing is collected this item should be placed into a paper bag with the appropriate labelling. This is to keep any trace of biological evidence intact before examination.

No presumptive tests can be performed upon physical evidence as it a visual piece of evidence. However if there is suspected chemical or biological evidence upon the evidence presumptive tests can be carried out on site by SOCO’s. Often there will be biological and chemical evidence upon these pieces of evidence therefore it is vital that SOCO’s carry out an accurate collection of evidence in order to preserve any further evidence that may be apparent upon analysation.

Footwear marks fall under the physical evidence category, and should be collected using a specific technique upon arrival of the SOCO’s at any given crime scene. If the mark is within mud or snow casting is a technique used in order to collect the mark. This involves using numerous chemicals forming a past and pouring the paste into the imprinted footwear mark. Once set a SOCO can then lift the print forming a 3D mark. If the mark is upon a flat surface an adhesive lifter is used, meaning a sheet of sticky like substance is used to collect the print. The sheet is clear allowing examiners to clearly see the pattern of the mark. Upon the lifting of the mark, this evidence should be logged into the chain of custody and bagged and tagged appropriately. Once this mark has been lifted scientists can examine the footwear mark and look for key factors, for example size of the shoe, make an educated guess as to whether it’s a female or male print, make and model of the shoe, height and weight of the suspect. These marks can be used within determining whether an individual committed the crime.

 



Physical Evidence within the OJ Simpson Case…

Within the murder investigation of Nicole Brown Simpson and Ronald Goldman there was numerous pieces of physical evidence. Some of this evidence was located within the scene however like the biological evidence some was found elsewhere pointing in the direction of OJ Simpson being the suspect within the investigation. This evidence consisted of footwear marks present within the scene, gloves which had biological evidence upon, socks which also had biological evidence upon and fibres present upon Ronald Goldman’s body. However with all this evidence pointing to OJ Simpson as the suspect he was still acquitted from the investigation. There was numerous reasons as to why he was acquitted however one factor was how the evidence was collected by the SOCO’s upon site.

Within the crime scene a bloody footprint was collected. Upon analysation scientists concluded that is was a size 12 male shoe print produced by a “Bruno Malgi” shoe. This type of shoe is a very expensive model which only a few have been made by an Italian designer. Upon the search of Simpson’s house officers found the same design of shoe. However as we know a common approach path was not used within this investigation therefore officers prints where located all over the crime scene as they tread blood and mud all over the property. This allowed the defence to argue that the print could have been any individual who attended the scene. With the officers and SOCO’s not following accurate procedures this evidence was inadmissible within court.

Blue fabric fibres produced from clothing where present upon the body of one of the victims (Ronald). Upon examination comparing one of OJ’s blue caps the fibres deemed to match. However this analysation is not always fully correct as fibres from other clothing items could easily match depending upon the fabric, therefore was not a solid piece of evidence. Upon the arrival of the police officers covered the bodies with a used blanket from inside Nicole’s property. This meant that any evidence found upon the bodies could not be admissible within court as contamination would have 100% occurred. Due to this fact the defence argued that these fibres could have possibly came from the blanket used to cover the bodies. This was poo police work as evidence from the bodies could not be used within court meaning key pieces of evidence was thrown out of court.

A glove was left within the crime scene, which had blood on. Upon analysation the blood had DNA markers of Simpsons and both the victims. Within investigation officers discovered that the victim Nicole had previously purchased the same type of gloves within the year 1990. This was a piece of evidence which was actually logged into the chain of custody however it was bagged with other pieces of evidence, suggesting that cross contaminated occurred. Upon an illegal search performed by Mark Fuhrman when climbing over his back wall he found a matching glove. However as this search was not warranted it raised suspicion of him planting this evidence. With the cross contamination and the planted evidence theory once again the defence tem argued this evidence out of the investigation after a lot of time spent discussing within court.

 

Overall the physical evidence which pointed to OJ Simpson as the suspect was overwhelming, however due to the lack of accuracy and professionalism when collecting and analysing the evidence most of the evidence was not viable within court. The collection and analysation caused many errors to occur such as the destruction of key pieces of evidence, cross contamination and the lack of documentation surrounding evidence.