Report On A) A Coke Can Of 330 ML And Mars Bar Chocolate Wrapped Paper Was Found At 11:11 Am
Agent (A) is forensic technician with the forensic team in crime central Tallahassee; she has been with the team for 25 years. Who collects different types of evidence that a crime scene investigators looks for when observing and processing a crime scene that can be used later for further investigations and court proceedings. There are testimonies that can be collected from any witnesses, items that are gathered at the crime scene which are considered physical evidence, biological evidence like fingerprints and trace evidence which may be small but could be very important for the process of figuring out what might have happened. When it comes to explosives the evidence found at the scene may also be present on the person or persons that were handling the explosive materials and the handlers may have left biological evidence behind on the materials as well. Biological evidence can include in this particular case bodily secretions which may be left behind by the suspects that are in custody. This can be there sweat, blood, saliva or urine and it is collected from the evidence and the suspect for later comparison. If a match is found on the evidence to the suspect in custody this would directly link him/her to the crime scene. Fingerprints are another important link to a crime scene if they are mistakenly left behind on the evidence by the suspect, there are three different fingerprint patterns and each fingerprint is unique to the person in question no two are the same. AFIS is the system that investigators use to determine if there is a match to the suspect and the fingerprint found at the crime scene or on any of the evidence in question. Biological evidence that may be present can be hair of the suspect(s) which has a unique pattern of DNA that can put a suspect at the crime scene if it is matched after collected from evidence (Trimpe, 2009). All of this collection needs to be done carefully with little disturbance to the crime scene to ensure the scene is not contaminated which would make the evidence hard to use for proof later on. Agent (A) has two team members are agent (b) (sketch artist) and Agent (C) analysis expert. The team was contacted at 10 o’clock am January 6th 2014 by detective (X) and asked to process the crime scene of a suspected terrorist plot. The scene was released to their team at 11:00 a.m. They began sketches of the scene of the crime immediately at 11:02 a.m. followed by a search of the crime scene at 11:09 a.m. The following evidence was collected at the scene with the time that they were collected:
B) 5 liter of bleach bottle (quality bleach standard) was found at 11:13 am
C) Starbucks cup was found at 11:15 am
D) Capri sun of 200 ml (empty) with orange straw in it was found at 11:16 am
E) Cables found at 11:18 am
F) Brown bottle of acetyl nitrile container found at 11:21 am
Agent (A) and the team members worked carefully when collecting the evidence from the crime scene as it is a fragile process and must be done carefully so that there is no cross contamination that could jeopardize the evidence collected. The most important thing to remember both for protection and guidance is known as Locards exchange principle which says that each time a person comes or goes from a crime scene something new is left behind. This is important when considering the team that will enter the scene and knowing that something was left by the suspects and the investigators job is to find it no matter how small. When evidence is found that can show the suspect present at the crime scene this is considered associative evidence and is usually some type of DNA or biological evidence (programs, 2012). This always in Agent (A) and the team worked carefully to process the scene without any interference or multiple visits. Once the evidence is able to be identified it will give them a clear answer to who was responsible for the crime or in this case suspected crime (Saferstien and Mclure, 2007). To come up with the answer to how things happened on the day in question pictures and evidence are gathered to reconstruct the crime scene later while developing a hypothesis. Agent (A) gathered control samples at 11:30 including dirt from the scene, and fibers that were located on the lids of the Starbucks cup and bleach container to compare to the clothing of the suspects to see if the same evidence is present which can put the person at the scene of the crime as well. Pictures were taken at the scene of the suspected plot for my team to be able to reconstruct the events later with complete accuracy. When the coke can and mars bar wrapper were found at 11:11 a.m. agent (A) chose to first collect any biological evidence that may have been left behind by the suspects. First the fingerprints that could be seen on the coke can were collected by using a fine powder that sticks to the print then lifting it with special tape and storing it in a paper envelope which agent (A) then marked with the time the print was lifted and place and placed it into evidence. Next agent (A) looked for any biological evidence like the suspects saliva around the opening of the soda and did this by swabbing the area carefully and placing this evidence in a place where it could dry. When collecting biological evidence like bodily fluids three techniques are available depending on the situation. Before applying any of these techniques cuttings would happen which is where a section of the evidence is separated for analysis (Ballou et. all, 2015). Next a technique called wet absorption is applied which is where a sterile gauze pad or something similar to the size of the area needed for collection is applied and then allowed to dry for later analysis and comparison. This is usually done at least two times to make sure that a sample is collected. The scraping method is another way to collect biological evidence by using a sterile blade to scrape the evidence onto clean paper and then it is packaged for analysis. The last technique is known as lifting which is the same technique used for collecting latent prints. There are many different types of fingerprints that can be gathered including fingerprints that can be seen by a persons naked eye or patent fingerprints or plastic prints with no help of equipment which can happen if the suspect has something on their fingers like ink or paint. If there are no visible fingerprints, like on the mars bar wrapper then investigators would look for latent prints which are the most likely to be found but require more effort because they are not visible without help. So this is what agent (A) with the wrapper when the agent could see no latent prints. Agent (A) then used the UV light the team carries and immediately discovered prints so agent (A) carefully lifted them with tape and collected the evidence in a paper envelope for further analysis and comparison later. The entry way and exit to the area may also contain these latent prints as they are left behind whenever a person comes into contact with any surface from natural oils produces by the body. If the investigator is looking for latent prints on a non-porous surface then they would use a powder that when it is applied it sticks to the oil and pattern that the print leaves behind. If there is a chance the fingerprint will smudge then investigators may use a magnetic powder that is applied without a brush to ensure the prints integrity is not interfered with. Superglue filming is another useful way to collect fingerprints for analysis which is used in the lab in an airtight tank and in some situations applied at a crime scene if the evidence is going to be shipped for analysis. On porous surfaces investigators would use chemical methods when searching for fingerprints which include unfinished surfaces or cloth. Iodine fuming is done in a chamber, silver nitrate reacts with the print and makes it visible in UV lights and Ninhydrine the most common fuming and requires spraying or dipping the print in the chemical, however this takes a long time to process and expose the print. After the prints are found on any of the surfaces at the scene of the crime or any of the objects seized as evidence the next step would be to take pictures of the fingerprints to ensure that evidence is not lost or tampered with and can be used for immediate comparison. The next step is to lift any fingerprints found which is done with rubber tape that is put on the evidence where the print is located and makes a permanent copy of the fingerprint on the tape. Last the fingerprints unique pattern will be able to be compared to the suspect’s fingerprints to either eliminate the suspect or link him/her to the crime (Sheridan, 2013). All of the evidence and the entry way and exit point can be processed for fingerprints as they are all possibilities when determining who might have been present and touching the evidence that was collected at the scene of the crime.
The five liter bottle of bleach that was discovered at 11:13 appeared to have visible fibers under the lid so those were collected by lifting with tape to reduce the risk of cross contamination. If hairs or fibers are found on any of the evidence it is possible to do an immediate collection when these can be seen with the investigators eyes by using tweezers to pick the fiber or hair and package it. Tape lifting is again a method used for this type of evidence collection and vacuuming is a solution if needed which captures the evidence on a filter. However vacuuming is not a usual or preferred method of collection because there is a high risk of contaminating the evidence and then it would be useless.
At 11:15 the Starbucks cup half empty was discovered by me and agent (A) carefully followed the same procedure for collecting any biological evidence the same as was done with the coke can and mars bar. The Starbucks cup also had a small hair on the lid which agent (A) collected with tweezers and placed in a paper envelope for DNA analysis. The suspects that are in custody would be considered as a possibility for valuable evidence as well. Reference samples are a collection technique that would be used to collect evidence from the two suspects for comparison with evidence retrieved at the crime scene. There are many different collection methods that may be used for comparison and the first is known as buccal swabs. This is where a cu tip is swabbed inside of the suspect’s mouth on his/her cheek to gather what are known as epithelial cells. Blood can also be drawn and contained in tubes with a preservative called EDTA or ethylene diamine tetra acetic acid. All biological evidence that is collected from the suspect(s) is usually dried before it is stored and then the most common method of packaging is in paper which yields the best results. If the biological evidence is liquid like blood it is stored in containers, properly labeled and then refrigerated as soon as possible (Webb, 2008). This will be comparable with any evidence including hairs, fingerprints and saliva found on the evidence collected from the scene. At 11:18 a black cable was found with no appearance of marks so the UV light was used to see if there were any prints and a partial unidentifiable so again agent (A) used tape to collect two partial prints from the tip of the cable for comparison with the suspect’s prints.
At 11:21 am a brown bottle of acetyl nitrile was found and processed for prints as there were no fibers found on it but a perfect handprint was detectable when I used the UV light to inspect it. It was then powder dusted and the print was carefully lifted and transferred to a paper envelope for later comparison.
The presence of the bleach and acid raised the teams suspicions as Bleach and any type of acid carry a warning that they should never be stored together as these can mix and create a very toxic gas making these two items very suspect and important evidence for collection (University, 2012), they can be analyzed for fingerprints and hairs or fibers however they probably do not contain any biological evidence because they are not items that a person would consume so the first step would be to determine if there are visible fingerprints, hairs or fibers. If nothing is visible or all visible substances have been properly collected investigators can next look for latent fingerprints using the available techniques. The rest of the items that were collected as evidence may contain fingerprints, hairs and biological evidence so they require a very thorough examination starting with visible signs of evidence and then collecting all biological evidence that can be processed at the scene and next at the laboratory. When acid is mixed with metal it can create a chemical gas and this makes the different metals at the scene very suspect. The coke can, Capri sun and even the wrapper might contain a mixture of the bleach and acytile nitrate which would show clear evidence that the two suspects were attempting to make an explosive mixture, this is called a binary mixture and proof might show that this was not just a coincidence that happened to look very suspicious (tased, 2015). Agent (A) contacted agent (D) an expert in explosive devices at the main lab in Michigan who informed the agent, a list of explosive device terms and descriptions would easily identify if the mixture of chemicals and other evidence could give the investigators cause to believe that this in fact was an attempt to make a bomb. All of the items that are listed have dangerous implications if combined in the right way which could in fact be the makings of an explosive device that could release dangerous toxic gas. The chemicals when combined create a dangerous gas and mixed with metal this is also a dangerous combination creating a binary explosion which is an explosive mixture that is capable of causing severe damage. The wire that was located and seen in the pictures taken at the crime scene is possibly able to be linked when combined with the chemicals and metals present if it contains PETN or RDX as it could be the detonation cord. PETN is also known as pentaerythritoltetranitrate and is a highly explosive material. RDX is a military plastic explosive device that can also be used for detonation. The wire would need to be collected for analysis by an expert in the area that could recognize the implications for possibility of being a detonation device. The reason that three different metals may have been found is because of what is known as an explosives train. This is a series of items that are all able to detonate with a purpose of initiating the explosion starting with the least sensitive and ending with the main explosive device. Last but not least there needs to be an initiator or the part of the device that begins the explosion. The Starbucks cup may be the container for one of the chemicals either the bleach or acid that when triggered would begin the process of mixing and initiating the final result an explosion (Saferstien, 2015).
Back at the lab, the team constructed an identical scene for comparison back at the lab and this was what the team concluded. Suspect one and two plotted to create a bomb that would go off on a bus in central London and because they were bio-medical students at a university not only did they have the knowledge to carry out the plan but also they had access to the materials needed like the acetyl nitrate and bleach in a large enough amount to sneak in and combine these with some will placed store bought items to create an explosive device capable of harming the people on the bus in London. The two gained access to the lab after attaining the other necessary items which included the coke can, candy bar wrapper, Starbucks cup, cable and Capri sun. After attaining the chemicals they needed to create the glass they laid out there plan just outside of the university classroom and were possibly beginning to construct the bomb when their plans were foiled and they were arrested as suspects in a plot to carry out this terrorist activity. If this hypothesis is able to be proven there should be trace evidence of the chemicals on the metals found at the scene and there could be biological evidence on the food materials that were consumed or fingerprints on everything that could connect the two suspects to the scene of the crime and probe their intentions to carry out the suspected bombing.
When an investigator processes a crime scene it is crucial that he/she takes the time to look for all kinds of evidence carefully. In this particular case as with any other the evidence can help investigators tell a story about what happened. First they need to take special measures to make sure they do not miss anything important. All of the evidence that was found at the crime scene led investigators to believe that indeed the suspects may have been involved in making an explosive. On their own each item found at the scene would not raise any alarm however to a trained professional when these are put together they can form a dangerous combination of materials capable of causing an explosion. The suspects in this case are innocent until it can be proven that they were in fact making an explosive so it is up to the team of investigators to process everything according to the rules. Photographs must be taken of the crime scene before anything is touched. After this fingerprints, DNA and fibers have to be looked for carefully to attempt to link the suspects to the crime scene or eliminate them as suspects. Last the suspects have to be studied and swabbed for DNA to compare to that which was found at the scene of the crime. If there is a match it puts the suspects undeniably in the place where they are being accused of being. The items found at the scene will also need to be examined to see if there is any indication they were being combined in a way that would lead investigators to further proof that this combination of items was no mistake and in fact was being used to make an explosive device. If a forensic team follows every step carefully it will allow them to recreate an almost exact rendition of events that happened the day the suspects were arrested and either put them as directly responsible parties, or prove their innocence.
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