Crime scene photography is an indispensable part of every case. It captures essential data and information, such as the condition of the scene just as the perpetrator left it, and can point to crucial information about the suspect. Also known as evidence photography, it’s a cost-effective way to provide additional, and very meaningful, evidence that can be used by all personnel involved.
One Medium, Many Uses
Photos taken of the crime scene and evidence are used in many ways and by many different personnel involved in a case:
• Investigators. Crime scene photos are used by investigators to tell a preliminary story of the crime—what happened, the type of weapon used, and each objects’ relationship. As such, crime scene photos are a valuable component used by every investigator to help solve a case.
• Attorneys. Each photo taken at a crime scene is also used by the attorneys as physical evidence in court, to either prove or disprove the case.
• Evidence Custodians. P&E custodians can use photos of individual pieces of evidence in the department’s evidence management system to add to its log, helping to maintain each item’s accountability and chain of custody.
With this much importance placed on these photos, it means that each evidence photographer must have sufficient knowledge in the mechanics, principles, and skills needed. In this quick guide, we’ll be discussing what every evidence photographer should know:
Principles and Procedures
There are several rules that every evidence photographer must adhere to when documenting a crime scene. They are the following:
1. Protecting the crime scene: Once the crime has been established, the location should be protected from any contamination to preserve it. Anything added onto the photographed scene will be considered a tampered crime site and will likely be deemed false evidence.
2. Assessing conditions: The photographer must consider weather and light conditions and fix their camera settings accordingly.
3. Capturing the scene: The photographer needs to document the scene using wide-angle shots. The photographer must then use close-up shots to capture the evidence’s relationship to the overall location fully.
4. Photographing the victims: The evidence photographer must highlight the victim’s location, position, injuries, and condition in each photo.
5. Photographing the evidence: The photographer must take each photo at the right angles to eliminate distance distortions. Each piece of evidence must be photographed with scale to demonstrate the size, and without scale to exhibit the evidence’s relationship to the overall crime scene. Photos of isolated pieces of evidence can also be taken to be uploaded to the log in the evidence management system.
6. Evidence markers: The photographer must take photos with and without evidence markers to confirm that no person or animal tampered with the crime scene.
7. Special imaging techniques: The photographer should consider using alternate light sources like blue lights to detect fingerprints, footprints, bite marks, and other such effects.
Taking Photos
Every evidence photographer must have the appropriate settings on their camera to capture good photographs.
1. Shutter: This specifies the duration that light is allowed to reach the digital sensor. Fast shutter speed suspends a moving object, which helps visualize its position at any moment. Meanwhile, slower shutter speeds highlight moving objects and results in blurring.
2. Aperture: This pertains to the lens’s opening size, which controls the brightness of light needed to properly take a photo. The aperture’s size is noted through its f-number or f-stop. F2.8 is the maximum aperture, while f32 is the minimum, but each lens has a different setup in terms of aperture settings.
3. ISO: This refers to the image sensor’s sensitivity to light. The lower the number, the less sensitive the image sensor is to light, making it suitable for well-lit conditions. A higher ISO is needed for dark areas or nighttime photography.
4. Flash: A photographer must have a camera equipped with flash or an external light source to illuminate the subject.
5. Depth of field: This is the area in front of and behind an object in focus. Larger apertures mean less depth of field; smaller apertures mean more depth of field.
6. Exposure: It measures the light that falls on a subject or the light the subject emits or reflects.
Basic Equipment Needed
Every photographer needs a proper set of equipment to produce top-tier photos that faithfully document a crime scene. They are the following:
• Digital single-lens reflex (DSLR) camera with 12 megapixels or higher, pop-up flash, hot-shoe, and flash or digital card
• Filters
• Lenses (normal, wide-angle, close-up)
• Electronic flash and its remote or sync cord
• Extra camera and flash batteries
• Tripod
• Film
• Locking cable release
• Notebook and pen
• Ruler
• Gray card
• Index cards
• Flashlight
Photos Help Manage Evidence
By following our tips above, your department’s evidence photographer can produce high-quality photographs that can be used by all personnel involved in a case. Evidence custodians can benefit by being able to add these photos to the individual evidence logs—a feature of robust evidence management software. By having a photo of each piece of evidence display next to its complete details, it helps custodians identify evidence, which aids in tracking and chain of custody.
Complete Evidence Management System
Looking for an evidence management system to help you manage each piece you find? Check out PMI Evidence Tracker™ for a comprehensive way to store and look up information about each piece of evidence, including its image. Have the ability to track your evidence quickly and securely. Get in touch with us today to learn more!
