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Have you ever seen a bag phone? That was the early cell phone. And that’s just one example of how technology has changed in the last thirty years. When I first started in crime scene investigation in the late 70s, we did not have digital cameras, camcorders, portable alternative light sources, superglue for processing fingerprints, personal computers, AFIS, or DNA capabilities. In other words, a lot of the technology and products that we now consider essential did not even exist then.
So, how did we get stuff done without the technology? In many ways, it was much more difficult and time consuming, but we used whatever technology was available. For example, we used Polaroid pictures to get instant shots. At one of my first crime scenes, we used a reel-to-reel black and white video unit that weighed about 40 lbs. You needed an extra person just to carry it around. The camera was attached to a six foot cable. A few years later, we switched to camcorders, which were much lighter and recorded in color, but quite large. Now we use digital cameras and digital camcorders that are lightweight, easy to use, and provide high quality images. Using cell phones and PCs, these images can then be transferred immediately back to the office so that other officers can begin their investigation.
Also in the 70s, we did not have truly portable alternative light sources to detect bodily fluids and some fibers that are not visible to the naked eye. While we did have lasers, they were very expensive. Each laser was so large that you needed a vehicle to transport it to the scene, making it impractical to use. Most lasers were kept in the crime labs. The first portable units for field work became available in the 80s, but they were still large and required 110V. They were also very expensive, ranging in price from about $20,000 to $25,000. Although the price eventually dropped, the units still had so many limitations that most crime scene officers did not use them. Instead, they relied on a visual inspection of the scene and took samples from any surfaces that might contain evidence. Finally, in 1995, the first portable, battery operated unit came out. A variety of models are now available; you can even get a unit for less than $200. These portable units are cost-effective, and they allow you to examine the scene much more thoroughly and efficiently. Alternative light sources are now to the point that they fit in an eyeglass case. You can have one with you on all cases you work to scan the scene for that evidence that will help make the case.
Processing a scene also involved some ingenuity on the part of the crime scene officer. For example, superglue became available in the 80s. We learned that we could use the fumes from superglue to develop latent prints on many surfaces, including the interior and exterior of vehicles. When the product first came out, we took the superglue, put it in a quart jar inside the vehicle, closed the vehicle’s windows and doors, and then left the vehicle and the superglue to heat up in the sun. From that point, we continued to devise ways to improve and speed up the process. One way was to use a bottle cap with superglue and place it on a piece of 1/8" steel, heated up to create the fumes. Another variation included using aluminum foil and a light bulb; a cup of warm water served as a source of humidity to help develop the latent prints and a chamber to contain the fumes. You can now purchase a complete system that is chemically activated to heat the superglue. These systems are especially useful for processing latent prints right at the scene.
One of the most important changes had to do with the computer. Personal computers are so commonplace these days that it’s easy to forget that they are a relatively new tool. In the 70s, the only computers were mainframes. There were no programs out there. If you wanted a program, you had to find someone to write it for you. As a result, these computers were not practical for everyday use. Instead, officers did all of their reports and forms by hand or on a typewriter. Presentations of evidence for court were also done manually, usually with 5X7 and 8X10 pictures. Once we had the PC and its set of existing programs, officers’ jobs instantly became much easier. Today, the evidence room is computerized, making it easy to track things for court. Officers save time by completing their crime scene reports and forms on their PCs. They can also quickly and easily transfer crime scene digital images and videos to their PCs and then create sophisticated PowerPoint presentations. We also have things like 3D imaging programs that make it easy to create crime scene diagrams.
Advances in computer technology have also led to vast improvements in fingerprint comparisons. Thirty years ago, if we got latent prints from a scene, we could compare them to a specific suspect’s prints we had on file. Once, we had a rash of burglaries. We got a latent expert to look at 50 possible suspect inked prints to compare with two latent prints recovered from the scenes. After several days of comparing the prints to 10 to 15 sets of cards on file, the expert identified the suspect and we solved almost two hundred burglaries. But if we hadn’t found a match the prints would have just sat in our files.
Then in the 80s, we got AFIS, and the process changed completely. First, we entered all of the latent prints for cases where we were still within the statute of limitations. Then we started looking for matches. At first we’d enter a set of prints and it would take a day to get results. In one case, though, we got a hit on an auto theft with only two weeks left before the statute of limitations ran out. That hit then tied into other cases. In another instance, we had a homicide in Topeka, Kansas. We entered the prints from the scene — no hit in AFIS. But six months later, we got a reverse hit when we arrested someone for DWI: the prints entered for the DWI matched the prints stored on AFIS for the homicide. AFIS continues to be an invaluable tool for crime scene officers. With its huge database of prints, you have an even better chance of gettinga match, and you get your results almost immediately.
Of course, the most dramatic change in crime scene investigation is in our DNA capabilities. When I first started out, we collected blood and whatever we could use as evidence with the technology and procedures at the time on sexual assault cases and various other types of cases where this type of evidence could be used. When DNA first became available, an old homicide case with semen was submitted to a DNA lab, but the sample was not large enough for the current technology. When the right technology became available, we got a match with a suspect on death row in another state. Unfortunately, he had been executed six months prior. We can now extract DNA from hair, saliva, fibers, latent fingerprints, etc. We can even take DNA from a parent and match it with DNA from a son or daughter. Once we have DNA evidence we can enter it into CODIS and look for a match. When you do get a match, the results are much more specific than what you get from blood type alone. Looking back at these last thirty years shows you just how much new technology and products have changed the field of crime scene investigation. Often, crime scene officers themselves are responsible for the changes. By using their knowledge and experience, they constantly take advantage of current technology to develop new and better techniques and products. Today’s crime scene officers depend on this sophisticatedtechnology and these advanced products to perform their jobs well.
So in many ways your job as a crime scene officer is easier now than it was thirty years ago. You still have to know what evidence to collect so that the lab can do its job. On the other hand, you have to keep up with the technology. If you don’t attend training sessions, you don’t learn. Take advantage of the knowledge available to you. Then you’ll be prepared for the nextthirty years of change.
Dick Warrington is in research and development and a crime scene consultant and training instructor for the Lynn Peavey Company. For the past several years, Dick has been teaching classes throughout the U.S. and Canada, trying to dispel some of those “you can’t do that” myths. Dick can be reached at email@example.com