Crime Scene Processing Protocol
by M/Sgt Hayden B. Baldwin, Retired
Illinois State Police

In the endeavor of completing a work task certain criteria to complete the work task is needed. Crime scene processing is no different in that respect than to other work related tasks such as exchanging a motor in a car, painting a landscape scene or preparing a meal. There are certain tasks related to each work objective. In the field of crime scene processing several books have been written on what these tasks are and how they should be incorporated into the field of crime scene processing. Yet each book varies only in the technique used, not in a change of the basic protocol used for the processing of crime scenes.

A few years ago I attended a lecture on "25 Ways to process a crime scene." It was probably the most boring lecture I've attended in years, but it did highlight one point that most of us have taken for granted. How do you explain to someone the mechanics of thoroughly processing a crime scene? It sounds simple, but in fact crime scene processing is a very intricate and interwoven multiple task function. It is difficult to explain to someone the exact protocol that will be used at every crime scene. Each crime scene is different and may require a different approach to processing the scene. However there is a basic crime scene protocol that should be adhered to in all crime scenes. These basic functions or tasks are as follows:

Interview is the first step in processing a crime scene. The crime scene technician must interview the first officer at the scene or the victim to ascertain the "theory" of the case. Basically what allegedly happened, what crime took place, and how was the crime committed. This information may not be factual information but it will give the crime scene technician a base from which to start.

Examine the crime scene as the second step in the protocol. Examine the scene for what? To ascertain if the "theory" of the case is substantiated by what the crime scene technician observes. Examining the scene to identify possible items of evidentiary nature, identify point of entry and point of exit, and getting the general layout of the crime scene.

Photograph the crime scene is the third step in the protocol. Photographing the crime scene to record a pictorial view of what the scene looks like and to record items of possible evidence. Crime scene photographs are generally taken in two categories, overall views and items of evidence.

Sketch the crime scene is the fourth step in the protocol. A rough sketch is completed by the crime scene technician to demonstrate the layout of the crime scene or to identify the exact position of the deceased victim or evidence within the crime scene. A crime scene sketch may not be completed on every case, however some form of sketching usually occurs in most cases, i.e., on a fingerprint lift card to identify exactly where the latent was recovered.

The last step in the protocol is to process the crime scene. Process the scene for what? The crime scene technician will process the crime scene for evidence, both physical and testimonial evidence. It is the crime scene technicians responsibility to identify, evaluate and collect physical evidence from the crime scene for further analysis by a crime laboratory.

The above five steps in the protocol of crime scene processing is intermingled with each other step. If the "theory" of the case dictates that the intruder forcibly entered the residence through a window then the crime scene technician will need to examine the window area for footwear patterns, toolmarks, trace evidence and latent finger prints. Upon finding such items of evidence the technician will need to photograph their location and possibly complete a sketch showing the exact location of the evidence or perhaps a sketch of the footwear pattern. This intermingling of the steps in the protocol will continue throughout the processing of the crime scene. Of course interwoven throughout these five steps is the recording of the crime scene by photographs, sketches, and field notes.

This protocol should be used in all crime scenes. Whether the crime scene is a recovered stolen vehicle or a multiple homicide where several crime scenes are involved the basic protocol is the same:


 If you have comments or suggestions, email me at