Collecting the Evidence

When it comes to a crime scene there are certain aspects that need to be carried out to ensure that all potential evidence is protected as well as not contaminated, also these aspects will protect the investigator as well. When it comes to the crime scene that is being searched the first protocol is to secure and protect the scene, this is carried out to ensure that all evidence is preserved and not contaminated. The next protocol is to determine the scene boundaries; this is carried out to find out how big the crime scene is and determine where the evidence will stop. After this the evaluation of possible evidence will be carried out and the reason for this is to try and find any information about how the crime happened, as well as the amount of people there, if there were any weapons and more importantly anything that gives a lead on the investigation. A write up of the crimes scene will be carried out as well and this is done because the scene can be viewed at the same time, this means that all the relevant information can be writ down and used for future reference in the investigation. Once all this is done there should be a photographer taking pictures of relevant evidence and the whole of the crime scene, this is carried out so that you can look back on these pictures at future date to help with the investigation as well as refresh your mind of what the scene looked like. Sketch of the scene will be carried out as well and this will link with the notes that will have been taken, once again this gives an overview of where evidence was and where key points where in the investigation. Once all this is done now the collection of evidence can be carried out, this is where you collect certain biological, physical or chemical evidence that can provide information on suspects or what type of crime it was; also this can give potential leads to issues going on in the victims life which may lead to speaking to close friends of the victim to gain information. After all this has been done a final survey will need to be carried out so that the crime scene can they be closed, this means that an overview of everything that has happened at the scene and everything that has been collected at the scene will have been recorded and sent off to a lab for inspection.

When collecting the evidence at a scene there are certain protocols that need to be carried out as well, these consist of photographing any evidence you find first and marking the evidence on the diagram being drawn. The next step is to place the evidence in its relevant bag, for example a knife would be placed in a plastic tube to prevent any further damage and also the plastic container stops the knife from penetrating through and injuring anyone. The reason why evidence needs to go in a certain bag is to stop any evidence that is present like blood, finger prints or substances getting damaged or lost. An evidence log will need to be carried out so whoever gets given that piece of evidence knows where it has come from and also instilled by the investigator who collected the evidence; ensure that all evidence is sealed as well.

There are three different types of evidence that can be collected at a crime scene and these three pieces of evidence are called Biological, Physical and Chemical. All of these pieces of evidence have certain meanings and are different, for example Biological evidence would be evidence that relates to the human body so evidence like saliva, fingerprints, sperm and blood would go in this category of biological evidence. Physical evidence would evidence left behind that is an object like a knife, gun, shoe or a footwear mark and chemical evidence would be evidence like drugs, gun residue and flammable liquids. Relating this to my case of the Billie-Jo Jenkins murder there was five pieces of evidence found and these where a tent spike with blood (Biological and Physical evidence) and a jacket, shoe and trousers with blood spots on Sion Jenkins from Billie-Jo (Biological and Physical) These where the key pieces of evidence that was found at the crime scene of Billie-Jo Jenkins and led to the first arrest of Sion Jenkins. The reason why Sion Jenkins was convicted from these pieces of evidence was due to the fact that he took a dodgy route to the Do It Yourself store (D.I.Y), Because Sion did a full circle of his estate before carrying on to the D.I.Y store; the investigators came up with the insinuation that it gave Sion enough time to bludgeon Billie-Jo which was the reason why there was so many blood spots on his clothes. The conclusion in court was that the impact of the tent spike was that much that the blood was spraying onto Sion Jenkins. It can be understood why the courts came to this conclusion as the route he took was conspicuous as well as the blood stains of Billie-Jo on him. Sion Jenkins defended himself by saying that the reason why these blood spots where on his clothes was because when he saw her covered in her own blood he picked her up and held her (as any concerned father would), Sion said that she portrayed blood from her mouth when he was holding her. This was then later proven in the second trial when forensics got involved and a full analysis was carried out on his clothes and what can happen when a person gets bludgeoned, which was a spray of blood that portray from the mouth when trying to breathe; this then led to Sion Jenkins being acquitted as there was no other evidence against him.

Analysis of Evidence at a Crime Scene

When it comes to collecting and analysing evidence at the crime scene there could be a wide variety of evidence, all evidence fits into three different types of categories and these categories are Biological, Chemical and Physical. So when it comes to collecting and analysing evidence those categories are what your evidence would be classed as, so when it comes to a crime scene any evidence that is within that boundary  would be valid evidence. Depending on the crime committed will depend on certain evidence at the scene, for example when there has been a murder committed there would be certain aspects to be looked at like is there a murder weapon near by, any DNA from a fight or struggle at the scene or where was the point of entry. There are many more pieces of evidence than those three pieces mentioned but when an investigator is at the crime scene there main priority is to protect the scene and any evidence  that is there, the investigator will want to find any potential leads on the murder and hopefully bring justice. So for the investigator to analyse evidence at the crime scene they need to look for any evidence that can help reenact the crime, so as an example the investigator would want to find the point of entry of the killer, how the killer has got from the point of entry to the victim. Where the point of attack has been carried out as well as where the point if impact was on the victim, how the body has fell and if the killer meant for the victim to die; has the victim died from the impact of falling onto a different object. This type of analysis of the crime scene helps provide a simulated scene in the brain of what is most likely to of happened, this then means if the investigator wants to look for any evidence linking to the killer then the simulated scene would help because the investigator will most likely know where the main places the killer would have been. Also coming up with the simulated scene can also help the investigators decide on what the killer was potentially wearing by using evidence found at the scene because if there are no fingerprints or footwear marks then the killer most likely gloves and shoe covers on to prevent evidence or following the simulated scene of the killer could lead to conclusive evidence that brings the investigation forward. Also when evidence is found at a crime scene some tests will be carried out there and some evidence will be sent to a forensic lab, the reason why some evidence will be sent to a lab is due to the importance of the evidence (the most important evidence is sent to a lab), the other evidence that is found may not be as important as others so this is where presumptive tests will be carried out. These presumptive tests are carried out to prove if the piece of evidence is what the investigator thinks it is, so as an example there is a red stain in the floor that could be blood. A presumptive test will be carried to prove if this evidence found is blood or not, once this as been done then further tests can be carried out. These presumptive tests also help the investigators to class the evidence as liable but further tests would need to be carried out for the evidence to prove victims or suspects. The presumptive tests also help reduce evidence because the the tests will prove if the evidence is liable and if it's needed to be further tested. 

In the Billie-Jo Jenkins case there was four pieces of evidence found which had blood stains on them and these four pieces of evidence where a tent spike, a jacket, a shoe and pants. The way that the investigators would know that the blood was present on these four pieces of evidence is due to the presumptive tests that get carried out, this is to provide evidence that there is blood present. The way that the investigators would carry out this presumptive test is by using certain chemicals, one of these chemicals is called phenolphthalein which is a colourless liquid that turns pink when it comes into contact with blood. Linking this to the Billie-Jo Jenkins case the investigator at the scene would carry out this test on all four of the pieces of evidence so that they would know that it's blood present, this means that the evidence found can be sent off to be further analysed. Another presumptive test that could of been carried out was the test for fingerprints and the reason why this could have been carried out is because the tent spike had to of been held, which means if the suspect had bludgeoned Billie-Jo then their fingerprints would of had to of been on the tent spike. To carry out this presumptive test you would have to use a fingerprint dusting kit which would have various colours of powder, a dusting brush and j-lar tape. This kit shows up any form of fingerprint which could then be used as evidence if one was found. There are other presumptive tests that could have been carried out in the murder of Billie-Jo Jenkins but they weren't relevant to my case.

Once the the evidence has been proved to have reliable evidence, it will get packaged in it's relevant bag and sent off to the lab for further evaluation, This further evaluation Will consist of looking for any other evidence that could be present. Other evidence that may be on the jacket could be hair, saliva, Gun shot residue, drugs and fingerprints, also when a piece of evidence gets sent off to a lab for further analysis depending on what type of evidence it is would determine on whether the investigator would look for the make and design of a piece of clothing or shoe if it was a piece of clothing or shoe. There are many pieces of evidence that can be found at a crime scene and most of them will usually have more than just one singular piece of evidence. In the Billie-Jo Jenkins case the jacket that was collected from Sion Jenkins with the blood spots present and was sent off to a lab to be evaluated, the evaluation was carried out by a scientist called Adrian Wain who found microscopic blood spots on Sion Jenkins clothes. By carrying out this analysis on the jacket of Sion Jenkins, the conclusion came to the point of that because the blood stains where so small that they came from a mist of blood that occurred due to the bludgeoning of Billie-Jo. This was then later used in court as evidence but when it came to the second trial more forensic analysis was carried which then supported the blood spray from Billie-Jo Jenkins as she was dying. The other two pieces of clothes had further analysis carried out on them and the result of these pieces of clothes being analysed Wain concluded the amount of blood spots that where found on his clothes where 150 blood spots all together, 72 on his jacket, 10 on his shoe and 76 on his trousers. With out this analysis being carried out further in a lab non of this evidence would have been found as the blood spots where microscopic and not viable from the naked eye, according to the crown court these where the most significant pieces of evidence in the trial.