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One of the most important aspects of any crime scene investigation is properly documenting the crime scene. This documentation provides a record of the evidence found at the scene and the observations of the scene itself at the time it was discovered. A complete and accurate record of the scene is essential for investigating the crime and for presenting the case when it goes to court.
Documenting the scene begins with the first responding officer. For any class of case, whether it’s a burglary, assault, accidental death, homicide, etc., the first officer on the scene is a major participant in the case. I started with the first responder because the actions of that officer effect the whole investigation and become key to creating a thorough documentation of the scene. Often, when the first officer arrives, the scene is chaotic, but he or she needs to assess the situation quickly and make a number of decisions. She must establish what she’s dealing with and decide what, if any, additional help she’ll need. She must secure and protect the scene, which are separate but inter-related duties. The scene must be adequately secured before it can be protected. The officer must also maintain control of the scene. If she doesn’t, witnesses may leave without giving statements. Suspects may disappear. Evidence may be lost or ruined.
Regardless of the type of scene, the first responder has the same set of responsibilities:
- Provide care for injured at the scene
- Secure and protect the scene
- Identify witnesses and suspects
- Maintain control of the scene
- Establish contact with headquarters
- Prepare notes to document actions taken and observations made
Keep in mind that evidence is anything that tends to prove or disprove any alleged fact. There are three basic types of evidence. Direct evidence establishes the elements of a crime through an eyewitness account of the criminal act. Indirect evidence is based on the fact being inferred from another fact known as circumstantial evidence. Physical evidence is any actual tangible thing, and is either animal, vegetable, or mineral. Courtroom difficulties concerning evidence and possibilities of contamination can be eliminated when a scene is adequately protected. Given what’s at stake, it’s vital that the first responder follow protocol and keep track of everything she sees and does, and then write notes. Her report is a key part of the scene documentation. The main methods of documenting the scene include the preliminary survey, the narrative description, the administrative notes, photography, sketching/diagramming, and the evidence recovery log. Each of these methods are part of a comprehensive approach to documenting your crime scene.
The Preliminary Survey records the condition of the scene as it was first found. For instance, you may note things such as doors and windows left open, missing items, ransacked rooms, etc. The survey can help you develop a general theory of the scene. The survey also establishes the extent of the area that needs to be searched and helps the crime scene officer determine what type of personnel and equipment may be needed for the investigation. For example, a crime scene may need to include the house, the backyard, and the surrounding area as part of the search area. Depending on the scene and the area to be searched, you may need things like extra lighting or special tools. If the search area includes a pond or a lake, you may need to bring in a boat. Depending on the type of evidence present, you may need to call in other types of experts.
Again, it’s important to control access to the scene. Any time someone moves in or out of the scene, you risk the possibility of transferring evidence through footprints, hair, fibers, etc. In order to maintain the integrity of the scene and the evidence, you want to have as few people entering and exiting the scene as possible. Do your best to prevent random physical activity through the scene. Use the survey to devise a plan of action. The preliminary survey helps establish what happened at the scene. In court, you have to be able to paint a picture for the jury. The preliminary survey can help you do that.
The narrative description is the documentation of the scene by the first responding officer. The narrative includes the officer’s written notes, along with any video recording if needed. The narrative may also include any photos, either through film or digital media, taken by that officer.
Administrative notes are straightforward and consist of the basic questions: who did what, why, how, when, and where. Again, careful and thorough notes are essential to keep track of everyone at the scene and all of their activities.
Photography allows you to accurately record the scene, using either film or digital media. To document the scene, you need to take overall, medium, and close-up shots. These photos should indicate the location, nature of the crime, the results, and the physical evidence created by the crime. If you can show all of that stuff, you’ve got it made.
One of the mistakes people make is taking just the close-ups with no scales in the photograph. For example, there might be blood spatter on a wall, and the crime scene officer only takes close-ups. Well, which wall was it on? Which room? Without the other shots, you can’t establish the location of the evidence. If you can’t figure out the location, it will be hard for the jury to figure out what happened. To avoid this problem, take photos from one corner to the other, and then zoom in. Use markers to make it easier to identify the evidence and to tie it to your report. Record all photography information in your report.
Once you’ve photographed the scene, you should also document it with a rough sketch and a finished diagram. These items are important parts of your documentation because they include all measurements and locations of items at the scene. If done correctly, the sketch and diagram provide the information needed to reconstruct the scene. They also give a good visual record for anyone who wasn’t present at the scene or for your own reference.
Start by making the rough sketch. The sketch should show the layout of the scene and indicate important items, but it does not need to be drawn to scale. The idea is to get a sense of the scene. Measure the length and width of the walls, the position of doors and windows, the location of the evidence, etc., and record the measurements on the sketch. Once you finish the sketch, use the measurements and other information to come up with the finished diagram. This final diagram should be done to scale using rulers and ink on paper, or on the computer using available software. The diagram should be accurate and clearly labelled so that it will make sense to others.
Evidence Recovery Log
The evidence recovery log documents evidence and its custody. Record this information on your department’s evidence custody sheet. Include identifying information such as the case number, date, and type of crime. Also list all evidence, item numbers, testing to be done, and your signature. Once the log is complete, evidence to be held should be sent to the property room. Items that need testing should be sent to the crime lab. As part of this log, you have to show every time something happens to a piece of evidence. If a prosecutor wants to see a piece of evidence, she has to sign for it. When she returns it, the property clerk or officer has to sign it back in. Documenting and tracking the evidence in this way allows you to establish and maintain the chain of custody.
Crime scene documentation begins when the first officer is called to the scene, and ends when the case closes. Done properly, crime scene documentation provides a detailed account of the scene. Take the time to do it right, and you’ll have the tools you need when your case goes to court.
Dick Warrington is in research and development and a crime scene consultant and training instructor for the Lynn Peavey Company. firstname.lastname@example.org