STUDENT NUMBER 2014OSC58443 Crime Scene Investigation (CSI) Level 3

STUDENT NUMBER 2014OSC58443 Crime Scene Investigation (CSI) Level 3

COURSE CODE – OSC532(V1.0)
COURSE CODE – OSC532(V1.0)
UNIT 5 – EVIDENCE HANDLING zoe wRIGHT
UNIT 5 – EVIDENCE HANDLING zoe wRIGHT
2015
2015

Introduction

This unit will be discussing the various packaging techniques in handling evidence taken away from crime scenes with the most appropriate ones being considered for each type of evidence found.
It will be discussed having the implications of poor packaging and the results which lead to contamination of all evidence if not packaged properly and the outcome when it is taken to court also the reliability of the CSI’s involved.
It is also the job of the CSI to make sure all health and safety procedures are in place before handling and taking any piece of evidence as there are varying risks involved like sharps, contamination of evidence, weather conditions other witnesses interfering with the scene, other personnel and any form of biological hazards. These must be taken seriously and analysed before any search.

Unit 5
1. Detail the forensic evidence that would have been taken away from the scene by the perpetrator.
The crime scene is probably the most important part of any criminal investigation. It is where forensic science starts. Locard’s Principle states that every contact leaves a trace (Locard, 1928). This is the primary rule of scene investigation – you are looking for ‘contact’ evidence that will help solve the crime. This trace may be in the form of a specific recoverable material, such as a chip of paint, or that of a mark or impression, such as a fingerprint. This physical evidence must be protected against loss and contamination and be collected in an appropriate manner so that its evidential value is not lost during its collection, nor on transfer to the forensic lab and onto the courtroom. The crime scene is therefore initially cordoned off to restrict access to the evidence, therefore protecting it against contamination.
Evidence such as vegetative material, soil, or broken glass might have been taken away from the scene. This evidence may establish a link between the suspect and that scene.
If the suspects shoe is either found at the scene or is recovered by police, the sole of the shoe can depict soil and trace material which can be used to link the suspect to the crime scene.
Linkage theory – A concept known as the four way linkage theory explains the connection between a crime scene, a victim, a suspect, and physical evidence. Theoretically, if associations can be established between two or more of these elements – scene, victim, suspect, and physical evidence – then the case may be resolved. The more associations established, the greater the probability of successfully solving the case. Example, if the investigation and a statement from the suspect indicate the suspect has never been at the location where the crime occurred, the scene should be carefully examined for any evidence that would prove that the suspect was present at the scene at some point in time. A suspect may have left behind fingerprints, footwear patterns, or transfers of trace evidence. At the same time, evidence such as vegetative material, soil, or glass might have been taken away from the scene. If a clear search of the scene reveals no evidence that the suspect was at the scene it may help focus the investigation on other suspects or situations.
Generally there are two types of transfer evidence; trace and pattern transfer evidence. Examples of commonly encountered trace transfer evidence includes fibres, glass, soil, and blood. Examples of pattern transfer evidence are imprint and impression evidence. Many times transfer evidence is a combination of trace and pattern components such as bloody shoeprints, greasy fingerprints, or fabric impressions.
Under certain circumstances, trace recoverable evidence can also lead to the identification of the source of that evidence. This can occur when there is a jigsaw puzzle type physical fit between questioned and control samples, where a DNA profile match is possible, or in cases where there are multiple types of matching recoverable trace evidence linking an individual to a place or to another individual.
2. Document the recovery of the evidence shown at the crime scene including packaging choice, method of recovery and risks involved with each item of forensic value.

As it has been mentioned in previous units, all evidence is located in and around the scene and then the item is packaged in the appropriate packaging, container, box, packet, bag etc. Once the best packaging has been identified for the sample it must be placed securely into the package. The appropriate packaging will depend on the size, shape, weight and substance of the item. To avoid contamination or losing the item the packaging must be taken to the sample not the sample taken to the packaging.
When collecting evidence you must understand; * The potential evidential value; * The purpose of recovering the evidence; * How much you will need; * What the evidence will be used for; * The analysis to be performed.
The evidential value, is the likely importance of the evidence in relation to the investigation – remember the evidence may support or disprove an individual’s involvement. Some types of evidence have greater importance than others, in terms of what the analysis will tell you. This is also important when considering the order in which you intend to collect the evidence. At any crime scene you must always maximise the recovery of evidence and minimise its contamination.
The order of collection requires thought and planning. Non – fixed trace evidence (e.g. fibres caught on a broken window frame) should be identified first, to prevent loss. Thereafter, they should be chosen to avoid contamination of other evidence.
The equipment taken to the scene will depend on the crime but the CSI’s kit should always include; * Latex gloves * Tweezers * Swabs * Forceps * Plastic bags * Cardboard boxes * Thermometer * Hand tools * Scalpels * Paper bags * Wrapping paper * Bucket with lid

2. Document the recovery of the evidence shown at the crime scene including packaging choice, method of recovery and risks involved with each item of forensic value. (Continued)
Once the evidence has been collected it must be appropriately packaged to prevent loss or contamination, and to ensure the continuity of evidence. You must be able to identify the exhibit that was collected at the scene by its label details and be able to account for its movements from the scene to the lab and finally to court. Every time the sample is moved, a log of its movements has to be recorded and whoever has transported it or examined it must sign the label attached to the sample to provide a written record of movement. In doing so the chain of custody (continuity of the evidence) can be accounted for.
Different types of packaging are; * Brown paper bags – these should be used for all items of clothing/fabric, unless the samples are wet, in which case they should be dried as much as possible or placed into polythene bags and placed into a cool box containing ice packs for immediate transportation to the lab for drying. * Polythene bags – (sealed with a heat sealer) – these should be used for the majority of items unless there is a danger of the item penetrating the bag e.g. broken glass. * Weapon tubes – these should be used for small weapons such as knives. * Cardboard boxes – these are useful for items that are fragile or may be broken e.g. footprint casts, or for items which could damage other packaging e.g. glass fragments. * Sterile medical swabs – these are used for bloodstain evidence and for collection of ‘intimate’ samples from a victim. * Sterile biological fluid containers – these are for the standard clinical/medical containers and are used for liquid blood or urine evidence. * Nylon bags for fire debris – these are used for the collection of volatile compounds which would diffuse through a polythene bag. The bag should be tied in a swan neck and secured with string. * Metal flame tins – these are used for the collection of non – biological liquids that are liable to evaporate e.g. petrol or alcohol. The tins have an inner push – top airtight seal and a secondary screw – top outer seal, to prevent any evaporation. * Glass phial – these are used for the collection of blood and urine samples. These need to be preserved with fluoride oxalate. This prevents samples from decaying in the phial and therefore the sample becoming useless. * Plastic pots – these are used for the collection of small items such as, cigarette ends, bullets and cartridge casings and broken pieces of knife blades. * Anti - static bags – these are for the collection of computer hardware, software and mobile phones.
For each type of packaging you should ensure that all sides are sealed and where appropriate that the edges are secured with tamper – proof tape over which you must mark your initials and date. Attached to all packaging must be a Criminal Justice Act 1967 label
2. Document the recovery of the evidence shown at the crime scene including packaging choice, method of recovery and risks involved with each item of forensic value. (Continued) indicating what the sample is. This must match what has been documented in the log book of whoever collected the evidence at the scene.
The label is usually attached to the packaging with sellotape and is initialled across the sellotape on to the packaging and should include; * Name(s) of the suspect(s) (if known) plus each of their date of births. * The exact identity of what the evidence is – for example 101 white tablets or black hoodie. * The exact location of where it was found. * The date when it was collected – which may be only a date or inclusive of time and date depending on the nature of the evidence. * The signature of the person who collected the evidence. * Identification mark specifically given to that sample of evidence.
The label should always be written clearly and with no scribblings or the use of correction fluid.
Types of forensic evidence collected:
Fingerprints – This is the most important form of evidence in terms of maximising recovery of evidence and minimising contamination. E.g. if there is a print in blood, it may be possible to swab the raised upper surface of the crust of the blood without disturbing the print itself. If the ridge pattern is clear then the evidence should be collected as a whole fingerprint for examination in the lab. Always photograph a fingerprint prior to lifting.
Footwear Impressions – These should always be photographed and should include two measurements at right angles to each other around the impression to indicate the size before the recovery. A cast using dental stone can be used to recover 3D impressions.
Hairs and Fibres – these are the most likely trace evidence to be lost at a crime scene. Recover these with tape lifts. In the case of large items I.E. sofas, the item should be examined at the scene.
Biological Fluids – There are many different types such as, blood, semen or saliva. All of these need to be collected using swabs if possible and seal in a tamper evidence bag, seal and label or in a sterile container.

3. Give reasons for your chosen methods of packaging discussing the issues faced by the CSI Team during the packaging process

When deciding what type of packaging is most appropriate under a particular circumstance, quite number of considerations need to be made; * Is there a health hazard involved? * Will the contents leak or filter through the material? * Will the contents decompose inside the container? * Is the packaging material suitable to freeze? * Will the item or sample puncture the container? * Does the item inside the container need to be seen by witnesses?
Health Hazards –
In every case involving the spillage or distribution of any bodily fluid there is always a potential health hazard. The hazard can be increased if the wrong packaging is used for storage. There are occasions, however, where the wrong packaging is used intentionally to temporarily alleviate the hazard.
Leaks and Filtration –
Paper or cardboard packaging will obviously allow the liquid from wet or even damp items to leak. This greatly increases the possibility of contamination between items especially if they are stored closely together. For this reason wet or damp items must be air-dried before this type of packaging material can be considered as suitable.
Puncturing the container –
Sharp instruments, such as knives and syringes, are regularly recovered during crime scene examinations. If such an item caused the packaging to become punctured, not only will contamination become an issue, everyone’s health and safety will be at risk. Such instruments must be packaged in suitable rigid containers. Deciding whether a cardboard box or a rigid clear plastic container is used will depend on the type of contact trace evidence that could be found during any subsequent examination.
Contamination –
This is one of the most important issues in forensic science and has the potential to occur throughout the investigation unless you are aware of how contamination can occur, consider where it might occur and then take appropriate steps to prevent it from happening.
This can occur at several points including; * At the crime scene. * During collection of evidence. * During transport of evidence.
3. Give reasons for your chosen methods of packaging discussing the issues faced by the CSI Team during the packaging process (Continued) * On submission of evidence. * During analysis. * On final storage of the exhibits.
The risk of contamination depends to some extent on the number of personnel who have entered the scene. At a volume crime scene there may be only a few people involved compared with a violent crime where police, members of public, CSI’s and emergency services may be present. Contamination can occur by events beyond your control, for example weather conditions. It can occur due to poor scene control, poor collection techniques, e.g. dusting prior to collection of DNA evidence, or finding that wet exhibits have leaked through the packaging on to other exhibits.
The chosen methods for recovering all evidence from the crime scene at the park are;
Sample Packaging Material Storage
Dry clothing Brown paper bag Cool, dry environment
Wet or damp clothing initially in polythene bag If can’t be dried then Until it can be dried then into it should be stored Paper bag. Frozen.
Footwear Brown paper bags. Each item of footwear Should be packaged Separately and stored In a cool dry place.
Fibre tape lifts Each strip of adhesive to be Dry environment. Sealed down onto a clear vinyl Sheet, marked with location from Where it came and placed into a Polythene bag.
Dry blood sample Original plastic sleeve from swab Freeze.
Swabbed from a surface and resealed. Sealed into
Using distilled water. Polythene bag with control swabs.
Wet blood removed from Swab dealt with as above. Pipette, Freeze.
Surface with swab or pipette. Sealed into polythene bag.
3. Give reasons for your chosen methods of packaging discussing the issues faced by the CSI Team during the packaging process (Continued)

Cigarette ends. Rigid polythene container. Freeze.
Tools or weapons. Protect blade or tip with polythene, Then seal in a strong rigid container. Dry environment.
Material cut by tools. Any suitable container that will Dry environment. Prevent damage to cut ends. Item Action should be Should be packaged to prevent loss taken to prevent cut Of other material that is paint, fibres ends rusting or And so on adhering to it. degrading.

It is easy to understand why the chance of contamination is higher in scenes involving a large number of personnel, but if the appropriate PPE (Personal Protective Equipment) is used before entering the inner cordon, then the risk is minimalised.
Appropriate PPE should include: * Scene suit – hood should be worn for serious offences. * Mob cap – to retain hair. * Face masks – avoid talking and manipulating the mask. * Overshoes. * Powder-free gloves – worn over the cuffs of the scene suit. By double gloving, one pair of gloves can be removed after handling a particular exhibit without the potential of contamination from bare hands.

Conclusion

This unit has covered such subject as to the different types of packaging used to collect evidence. Each type of packaging has to be the right ones and paramount for each type of evidence or some of the samples can become contaminated or lost due to lack of proper packaging.
The CSI has to make sure that each piece of evidence has to be securely packaged and signed on the seals and that the Criminal Justice Act labels are correctly completed and stuck onto the evidence packaging.
The unit has also discussed the chain of evidence principle, making sure that every form is correctly signed, and filled out. This is imperative to each sample as there will be no chance of incorrect evidence when it goes to court.

References

Mozayani, A. (2010) The forensic Laboratory Handbook Procedures and Practice London, Springer
Pepper, I (2010) The Crime Scene Investigation: Methods and Procedure London, McGraw – Hill Publishing
Sutton R & Trueman K (2009) Crime Scene Management: Scene Specific Methods London, John Wiley & Sons
I. Langford, Alan, (2010) Practical Skills in Forensic Science, CPI UK, Essex, Pearson Education Limited
F Barbara Imeier, (1998) Crime Scene Investigation, Libraries Unlimited Inc.
Henry C. Lee, (2001) Henry Lee’s Crime Scene Handbook, Academic Press Inc.