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Today’s high-tech world greatly increases our ability to put the “bad guys” in jail. But technology only takes you so far. As crime scene officers, we have to expand the role we play in order to take full advantage of the technology out there. In many cases, this means increasing our training in more areas so that we are ready for whatever challenges we face in the field—that’s why in the title of this article I refer to the crime scene officer as the Forensic Crime Scene Officer to emphasize this new level of responsibility.
To begin with, a crime scene officer must first know the capabilities of the lab. When you have this knowledge, you understand what type of evidence to look for and what type of evidence you need to collect. And you also know when you need to call in other experts. Remember, you don’t want to lose a case because you’re too proud to ask for help. This is a mistake I’ve seen too often; don’t let it happen to you. Also note that the more equipment you have with you, the more you will expand your ability at the scene to locate the evidence.
Whenever you’re at a scene, collect as much forensic evidence as possible. Often you won’t know which piece of evidence will be the key until you have all the pieces. Then, bingo, you find the right one, it hits, and you make your case. Also, if you don’t properly identify, collect, and document the evidence from the scene, the people back in the lab won’t have anything to work with. Depending on the scene, look for things like hair, blood, semen, fibers, paint chips, pieces of paper, soil samples, tree seeds, broken glass, etc. These small items can be crucial to DNA and other microscopic examinations.
In addition to trace evidence, you should also look for evidence that you will need to cast. These include tool marks, footprints, and tire tracks.When you find this type of evidence, you need to photograph it and then be prepared to make castings. Again, this evidence can prove invaluable for your case, so it is essential that you know how to deal with it at the scene.
These days, crime scene officers are capable of doing more forensic work right at the scene. For example, an officer can use Hexagon OBTI to check if a blood sample is human or animal. A positive test for human blood provides immediate information that the officer can use while continuing to process the scene. Officers can also spray Bluestar solution on surfaces to look for blood that a suspect may have tried to clean up. The Bluestar fluoresces if it comes in contact with blood; if you get a flash, you can then photograph it as evidence.
In addition, crime scene officers must also function like surveyors because they need to provide documentation, including diagrams, of each crime scene. The documentation and diagrams are needed to support court cases and to reconstruct the crime scene. Many mapping systems are now available to make this part of the job easier for crime scene officers. But in some cases, such as when the crime scene occurs in a remote area or along a coast line, documenting a scene properly so that it can be located again easily can be challenging. I once had a case that occurred in deep woods without any good landmarks. In order to come up with specific reference points, we buried a metal spike next to the scene.We then took compass headings from the spike and made additional measurements from that point. This gave us enough information to diagram the scene for court and allowed us to find the exact spot again in the future. For difficult scenes you can also use GPS to provide reference points. The effort you put into doing this job right will be well worth it.
As technology advances, crime scene officers must advance their knowledge and training. Some key areas to focus on include bullet trajectory, blood spatter, and the proper way to collect sensitive evidence such as computers and drugs. Without the right training, valuable evidence can be lost or damaged, and a case can be jeopardized. For instance, some suspects now set up their computers in such a way that the hard drive will crash if it is moved improperly, so it’s vital to stay up-to-date. Remember, the more you can do in the field, the more the scientists in the lab can do to verify your work. And in the end, all that hard work will result in a strong case for the prosecution.
Dick Warrington is in research and development and a crime scene consultant and training instructor for the Lynn Peavey Company.