READ: Collecting and Packaging Evidence

Collecting and Packaging Evidence

Collecting and Packaging Evidence

Once evidence has been located and completely documented it will need to be taken to a lab for further testing or stored in a secure evidence locker. Evidence is usually submitted to the lab in person or through the mail. Certain types of evidence such as explosives evidence and other hazardous evidence cannot be mailed. Depending on the type of evidence the entire piece of evidence may be collected, or a just a sample might be collected. There are many different types of evidence that investigators encounter in a crime scene and each type of evidence needs to be packaged correctly so that it does not become damaged while being transported or stored. The packaging of specific types of evidence will be covered as we discuss each type in the course, but we will learn about general materials and procedures used for packaging evidence here.

Investigators bring packaging materials with them to the crime scene. Usually the necessary materials are compiled into a kit and carried in the back of a vehicle or in a larger crime scene investigation truck. It is important to have all of the materials needed for packaging different types of evidence on hand so that evidence does not become damaged. Some necessary items include paper and plastic bags, plastic and metal containers, and paper envelopes to store evidence in. Tape, forceps (like tweezers), and swabs are needed for picking up smaller pieces of evidence or taking samples. It is also a good idea to bring flashlights and magnifying glasses to the scene to make finding and packaging evidence easier.

Other special equipment is used to collect certain types of evidence. Powders and brushes for dusting fingerprints are often necessary. Materials for making casts of tire or shoe impressions may be needed. There are also special lights and filters that can be used to make evidence that is hard to see more visible. Sometimes it may be necessary to complete chemical testing on substances found at the scene. Materials for these tests should also be brought to the scene.

An evidence collection kit should also contain personal safety equipment. Gloves, shoe covers, hair nets, lab coats, face masks, full body suits, goggles, safety glasses, and antiseptic washes should all be included in any evidence collection kit. Safety equipment protects both the investigators and the evidence. The investigators are protected from touching hazardous chemicals or contracting an infectious disease at the scene. The evidence and the scene are protected from possible contamination that could come from the investigators hands, clothes, or hair.

Each piece of evidence needs to be properly labeled. Evidence tags, biohazard labels, pens, and markers are all useful to have in order to correctly label evidence. Evidence needs to be labeled with information such as the case number, the date and time it was collected, the location, and the name of the person that collected the evidence. The label should also include a description of the evidence that is placed in the container. The evidence should also be labeled with the item number. The item number is the number on the evidence marker that was placed next to each piece of evidence. If the evidence is a sample of body fluid, or a substance that could contain harmful viruses or bacteria, it should be marked as a biohazard. 

Chain of Custody

Chain of Custody

In addition to being properly labeled, the chain of custody must be maintained for each piece of evidence. The chain of custody is a record of all personnel who had possession of a piece of evidence. Every time evidence is transferred from one person to another the transfer must be documented. There is a log on the evidence packaging, or a log that is kept with the evidence to document every person that had the evidence at all times. The person who transferred the evidence and who they gave it to, along with the date and time, must be recorded every time evidence is transferred. Maintaining the chain of custody is important so that when a piece of evidence is used in court, there is no question about where the evidence has been since it was taken from the scene. The chain of custody helps to prove that the piece of evidence was the same exact piece of evidence that was taken from the scene. If there is any question about this the evidence may not be allowed to be used in the case.

An example of how the chain of custody works is described below:

Officer Miranda Johnson finds a jar of white powder at a scene. She packages it and records her name as the person who recovered the evidence. She records the time the evidence was found. She then takes it to a lab and gives it to the lab technician, Derek Harris. Derek will test the powder to determine what it is. Derek will put his name on the log with the date and time of transfer. When Derek is done with his testing he puts the evidence back in the package and gives it to lab manager Susan Blake. Susan puts her name on the log with the date and time and stores the evidence in a secure locker until it is needed.

If there is any debate in court about whether the powder that was tested was the same powder at the scene, the chain of custody helps prove that everyone involved kept track of the exact powder from the scene. The chain of custody accounts for where the powder was at all times. It is best to keep the transfers of evidence to a minimum so that the chain of custody is clear. The fewer the people who handle the evidence, the better.

Search Warrants

Search Warrants

Another major consideration when it comes to collecting evidence is ensuring that the search conforms to the 4^th amendment. The 4^th amendment of the U.S. Constitution protects citizens from unreasonable search and seizure. Basically this means the police and investigators need a search warrant in order to search for evidence. In some cases, if evidence is obtained without a warrant it may not be allowed in court. Sometimes investigators will have to wait to receive a warrant from a judge before they can search for evidence. It is important that investigators have a warrant so that the evidence will be allowed in court.

There are several exceptions where a search warrant is not required. If the search is being conducted because of an emergency, such as a person obviously needing help inside a home, a warrant is not needed. If there is reason to believe that evidence may be destroyed before a warrant can be obtained, a warrant is not required. If the person who owns the property allows the officers to search the property, a warrant is not needed. 

Importance of Documenting Evidence

Click HERE to watch a video that explains the process of documenting evidence and why it is important.