Procedures for the Collection & Preservation of Evidence

Procedures for the Collection & Preservation of Evidence

With any crime scene there are procedures in place that are required when collecting evidence. The procedures include collecting the evidence using the right equipment, correctly bagging the evidence in and tagging, labelling and sealing the evidence correctly. These procedures ensure that evidence is preserved correctly and is not contaminated before any forensic analysis takes place.

Securing the Scene

The scene of the crime has to be secured usually by the First Attending Officer (FAO), this will be done by using police take and sectioning off the crime scene, this is to prevent anyone from entering the scene and tampering with the evidence. This is important to ensure the crime scene is kept safe and that any evidence will be preserved until it is collected.

In the case of Christine Jessop the location of where the murder occurred is still unknown however the body was handled by another county due to the location of where the body was found, this meant that job was done correctly and the scene of the body was secured however this is due to it being handled by another state.

Collection of Evidence

Before evidence is collected it should also be photographed using scales so that the size of evidence can be obtained/estimated from looking at the photographs. When collecting evidence it’s important that scenes of crime officers, SOCO’s, wear personal protective equipment, PPE, such are gloves and footwear protection, this is to ensure that no contamination can occur, if contamination was to occur the evidence would not be valid making it useless in court. Collecting in the correct manner and using the correct equipment is also vital when collecting evidence as it could affect the evidence if not packaged correctly or harm someone. For example knifes and other weapons need to be collected in a plastic tube and sealed, they will need to be handled with plastic gloves when placing them into the container, they’re placed into the plastic container and sealed so that they are unable to cause any harm to those handling the evidence. The reason behind specific pieces of evidence being collected using specific equipment is to prevent the evidence from being damaged or contaminated during the collection, preserving the evidence.

When relating this to the case of Christine Jessop there were only 3 pieces of evidence these were secured, one out of the boot of Guy Paul Morin’s car, fibres matching Christine’s Jumper, and two from the body of Christine Jessop, semen found in her knickers and hair found in her necklace, the pieces of evidence found at the scene of the body were correctly collected however the knickers were incorrectly tested on and incorrectly stored meaning that the results of the tests were invalid. The fibres were found on a blanket, this was then stored correctly however were left in the boot of a patrol vehicle over the weekend and no entered into the chain of custody straight away, this meant that potential contamination could have occurred or even tampering of evidence. The only evidence that was correctly collected and stored was the hair found in the necklace. If all 3 pieces of evidence were to be correctly collected and stored and entered into the chain of custody the evidence gained from it could’ve been useful and benefited to the case potentially helping find the real killer. Unfortunately there was no murder weapon found and no other evidence that could’ve helped the case with other evidence.

Bagging of Evidence

Once any evidence has been identified and collected at a crime scene it is vital that it be placed into an evidence bag or container then sealed to prevent tampering and contamination occurring. There are two types of evidence bags available to place evidence into depending on the type of evidence it is, there are also different sizes of bags that can be used. The two types of bags are, Plastic bags which can have test tubes containing swabs of biological evidence placed into them as well as potential items that might have finger prints on, for example a bank note. Paper evidence bags can hold biological evidence such as clothing that is covered in blood. Paper bags are more effective than plastic bags when having certain biological evidence placed into them as they allow the fluids to dry if still wet and prevents condensation to occur which would cause the evidence to deteriorate, this would be occur in a plastic bag. Boxes and tubes can be used at a crime scene to place weapons such as knives or hammers into, these boxes allow the evidence to be secured to prevent it from moving around and also as the boxes are reinforced unlike the bags it can prevent the weapons piercing through and potentially harming someone. Containers can also be used at a crime scene to place evidence such as drugs in, the containers can be sealed to prevent contamination occurring and also prevent the evidence being tampered with.

When relating this to the case of Christine Jessop there were only 3 pieces of evidence these were secured, one out of the boot of Guy Paul Morin’s car, fibres matching Christine’s Jumper, and two from the body of Christine Jessop, semen found in her knickers and hair found in her necklace, the pieces of evidence found at the scene of the body were correctly collected and bagged. However the knickers were incorrectly stored and the fibres found in the car were not entered into the chain of custody as they were left in a patrol vehicle over the weekend.

Tagging & Labelling Of Evidence

Once evidence has been placed into the appropriate containment it must be tagged and labelled. These tags should include; their name, the case number relating to the crime scene and the exhibit number of the evidence. The tags can be attached to an evidence bag however not always needed as on plastic evidence bags there are spaces to write the information onto the bags themselves. The tags also have space for any officer who handles the evidence, this is called the chain of custody and is an effective measure to allow for evidence to be traced from person to person all the way back to the original scenes of crime officer who collected the evidence at the crime scene. This helps to remove the chances of evidence getting lost or placed with other evidence not related to the case or even tampering of the evidence.

When relating this to the case of Christine Jessop the three pieces of evidence were correctly tagged and labelled after being bagged, and correctly filled out with the chain of custody as well.

Chain of Custody

This procedure is used to follow and trace back the evidence found revolving the case. The evidence collected by SOCO’s would be handed to the exhibits officer present at the crime scene, the exhibits officer will then log the information about the evidence onto an exhibits log sheet, such as what it was and the submitting officer’s name and date and time. This procedure is carried so that if the evidence is received in the laboratory and appears to have been tampered with or the evidence goes missing, there is a record that can trace back to who last handled the evidence, as this will be recorded on the chain of custody.

When relating this to the case of Christine Jessop out of the three pieces of evidence two pieces of evidence required the chain of custody to be looked into as the fibres and the knickers both had errors occur with them as the fibres were left in a patrol car over the weekend and errors occurred with the knickers when testing, the chain of custody allowed them to find out where these problems occurred and find out as to why.

Types of Evidence

There are 3 types of evidence that can be collected from crime scenes; these are biological, chemical and physical evidence. Each of the different forms of evidence is analysed differently and can provide different information regarding a crime that has occurred at specific crime scenes. These pieces of evidence would then be analysed within the forensic labs to be used as evidence.

1.      Biological

Biological evidence is made from organic materials. The types of evidence within this category include bodily fluids such as blood, semen, saliva and sweat usually found in the form of a fingerprint. This category of evidence also includes hair and skin tissue.

When relating this to the case of Christine Jessop there were only two pieces of biological evidence, these were a hair found on Christine’s necklace and the semen found in her knickers. When forensic scientists were performing their analysis of the semen found they made a mistake in the testing causing an error, as well as an error with the testing they incorrectly stored the evidence meaning it could no longer be used. There is no reports of the hair ever being analysed.

The hair that was found on Christine's necklace was collected using tweezers and placed into a plastic tube, this was to ensure the hair wasn't lost in the bag, this tube was then sealed and placed into a plastic bag, this was to ensure the evidence was not tampered with and was kept safe. This is the correct way to collect and store the hair, however it was lost in transport and was never tested.
The knickers were collected and placed into a brown paper bag, this was to ensure that no condensation occurred and affected the evidence. this bag was then transported to the labs for testing, however once it arrived at the labs it was incorrectly stored causing the semen to become invalid, the knickers should have been correctly stored in a fridge in the labs, this would be to preserve the semen. The only error in the collection and storage of the kickers was the storage, this caused this vital piece of evidence to become invalid.

2.      Chemical

Chemical evidence is evidence that is composed of chemical elements and compounds. The types of evidence within this category include Gunshot residue, drugs, paints and toxins such as poisons.

When relating this to the case of Christine Jessop there was no chemical evidence present at the crime scene.

However if there was any chemical evidence found at the scene it would have been swabbed by a scenes of crime officer, this swab would've then been secured in a plastic evidence bag to ensure tampering never occurred.

3.      Physical

Physical evidence includes objects and items that are collected at a crime scene to be analysed. Examples of physical evidence include items such as footprints, video footage, clothe fibres and a weapon.

When relating this to the case of Christine Jessop there was only one piece of physical evidence found, this was a red fibre matching a jumper owned by Christine, however when Christine went missing its believed she wasn’t wearing a jumper and no jumper was found with her body. Just like the hair there was never a report confirming that this fibre was a match as there was no jumper to compare to making this evidence useless.
This fibre was collected using tweezers and placed into a plastic tube, this was to ensure the hair wasn't lost in the bag, this tube was then sealed and placed into a plastic bag, this was to ensure the evidence was not tampered with and was kept safe. This is the correct way to collect and store the hair, however the officer collecting this evidence had been reported to have just been in the Jessop residence and in uniform and no PPE upon collecting this evidence.