Bloodstain Photography
George Schiro
Forensic Scientist
Louisiana State Police Crime Laboratory
Once the walk through is completed, the notes must be supplemented with other forms of documentation, such as videotape, photographs, and/or sketches.
See also the instructional videos on "Crime Scene and Evidence Photography"
Videotape can be an excellent medium for documenting bloodstains at a crime scene. If a video camera is available, it is best used after the initial walk through. This is to record the evidence before any major alterations have occurred at the scene. Videotape provides a perspective on the crime scene layout that cannot be as easily perceived in photographs and sketches. It is a more natural viewing medium to which people can readily relate, especially in demonstrating the structure of the crime scene and how the evidence relates to those structures.
The value of videotaping blood evidence is that the overall relationship of various blood spatters and patterns can be demonstrated. One example of this could be a beating homicide. In this case, videotape can show the overall blood spatter patterns and how these spatters are inter related. The videotape can also show the relationship of the spatters to the various structures at the crime scene. In cases where the suspect may have been injured (such as stabbing homicides), the video camera can be used to document any blood trails that may lead away from the scene. If videotaping indoors, the camera can show how the various areas are laid out in relation to each other and how they can be accessed. This is particularly valuable when recording peripheral bloodstains that may be found in other rooms. The high intensity light source can also be used for illuminating the bloodstains to make them more visible on the videotape.
Whether a video camera is available or not, it is absolutely essential that still photographs are taken to document the crime scene and any associated blood evidence. If a video camera is available, then still photography will be the second step in recording the crime scene. If video is not available, then still photography will be the first step. Photographs can demonstrate the same type of things that the videotape does, but crime scene photographs can also be used to record close up details, record objects at any scaled size, and record objects at actual size. These measurements and recordings are more difficult to achieve with videotape.
Blood evidence can be photographed using color print film and/or color slide film. Infrared film can also be used for documenting bloodstains on dark surfaces. Overall, medium range, and close up photographs should be taken of pertinent bloodstains. Scaled photographs (photographs with a ruler next to the evidence) must also be taken of items in cases where size relevance is significant or when direct (one-to-one) comparisons will be made, such as with bloody shoeprints, fingerprints, high velocity blood spatter patterns, etc. A good technique for recording a large area of blood spatter on a light colored wall is to measure and record the heights of some of the individual blood spatters. The overall pattern on the wall including a yard stick as a scale is then photographed with slide film. After the slide is developed, it can be projected onto a blank wall or onto the actual wall many years after the original incident. By using a yardstick, the original blood spatters can be viewed at their actual size and placed in their original positions. Measurements and projections can then be made to determine the spatters' points of origin.
About the Author
George Schiro has over 35 years of experience as a forensic scientist and crime scene investigator. He has examined evidence in over 4300 criminal and civil cases. While most of these cases have been in Louisiana, he has also consulted on cases in 31 other states, for the United States Army and Air Force, New Zealand, Panama, and the United Kingdom. He has also testified as an expert witness in over 215 trials in 31 Louisiana parish courts, Maricopa County Arizona, Washington and Pope Counties Arkansas, San Bernardino County California, Escambia and Lee Counties Florida, 17 Mississippi counties, St. Louis County Missouri, Clark and Lee Counties Nevada, Bernalillo County New Mexico, Bronx and Queens Counties New York, Three Texas counties, Shelby County Tennessee, Cabell County West Virginia, Campbell County Wyoming, federal court (Louisiana Middle, Nebraska, and Middle Tennessee districts), U.S. Court-martial (Luke Air Force Base) and two Louisiana city courts.
Specialties: Crime Scene Investigation, Crime Scene Reconstruction, General Forensic Science, DNA Analysis, Serology, Bloodstain Pattern Analysis, Shooting Reconstruction, Shoeprint Identification, Hair Examination, Latent Print Development, Fracture Match Analysis
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