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Introduction to Incident Scene Photography New Mexico State Police Criminal Investigations Section Crime Scene Team. Learning Objectives. Identify the requirements for a photo to be admissible in a court of law Identify the elements of a good, technical photograph. Learning Objectives.
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Introduction to Incident Scene Photography New Mexico State Police Criminal Investigations Section Crime Scene Team
Learning Objectives • Identify the requirements for a photo to be admissible in a court of law • Identify the elements of a good, technical photograph
Learning Objectives • Identify the elements of technical photography • Demonstrate how to properly photograph footwear impressions • Demonstrate how to properly photograph tire impressions • Demonstrate how to properly photograph latent prints
Introduction • For police officers, photography has become the primary way of documenting crime & traffic collision scenes. • Photography is a combination of art & science.
Why Take Photographs At A Crime Scene? • Photographs document the scene in a way people can understand. • Photographs can be used to recreate the crime and to prove or disprove a suspect’s explanation. • They can help a jury understand where and how the crime was committed. • A picture is worth a thousand words.
To Be Admissible in Court • Fair • Not biased or prejudicial • Must not appeal to the emotions of the jury • Accurate • Technically correct • Form, Tone, Color and Scale Test
To Be Admissible in Court • Relevant • Of value to the court and jury in making decisions • Chain of Custody must be maintained • The photo must be identified • Introduced in court by a person who is qualified to identify it Test
NM DPS Digital Imaging Policy • Capture • Take pictures in accordance with the manufacture's instructions, DPS policy and your training and experience. • Do not view the images (other than by the camera's built-in monitor) prior to the images being transferred to CD. • Storage • Store the images onto a permanent media (CD) as soon as possible. Once the images are stored onto a CD, the CD will be treated as original evidence...
NM DPS Digital Imaging Policy • The CD should be labeled with a permanent (Sharpie) marker: • Case # • Item # • Photographer's name • Date images were captured & date transferred to disc • Location where the images were captured • Dissemination and image enhancement • Before any enhancements are made, you must make a working copy of the CD. • An “Image-Processing Log" shall be kept for enhancements. The log will detail all steps used to obtain the enhanced image. The software (& version) shall be documented. • Software shall be generally or scientifically accepted in the photography community as a valid tool for enhancement.
Labeling the Disc as Evidence • Label as Original • Case# • Item# • Case Agent • Description • Date taken • Date to disc • Photographer
Elements of a Good, Technical Photograph • Must be correctly exposed • Have maximum depth of field • Have an accurate perspective • Be in sharp focus Test
Impression Evidence • Orientation (overview and midrange shots) • Show where the impression is located in the crime scene. • Close-up • Use a scale on the same plane as the impression. • Keep the film plane parallel to the plane of the impression • MUST USE A TRIPOD • Lighting • Block out ambient light with a large piece of cardboard and use a strong light source at oblique angle to show the best detail in the impression.
Tire Impressions • Photograph tire impressions in sections showing one circumference of the tire. • Taking overlapping photographs, with a tape measure, parallel to the tire impression.
Photography of Very Important Vehicles • Exterior Photos • Use the “21 point” method • Sometimes it is not possible to get all 21 photos • Do your best • If you have multiple vehicles involved in a crash • Take the standard over-view photos of the ENTIRE scene first • Then, take 21 photos of each vehicle individually • Then, take mid-range and close-up photos of the evidence
21 Point Method Edge Front Edge Diagonal Diagonal Front Edge Front Edge Front Axle Front Axle Side Side Rear Axle Rear Axle Rear Edge Rear Edge Diagonal Edge Edge Diagonal Rear These 20 Photos + 1 Photo Directly Down = 21 Photos
21 Photos of Each Vehicle • You will not be able to get all 21 shots due to the position of the vehicles • Just do your best
Fingerprints • Should be photographed before lifting • Orientation shot to show location • Consider using black & white film for greater contrast • Macro or close-up lens • Scale on the same plane must be used • 90 degree shot • Use a tripod
Tool marks & serial numbers • Orientation photo • Evidence at the scene • Close-up photos • Use a scale on the same plane as the evidence • 90 degree photo • Oblique light to create small shadows in the detail • Use a tripod.
Impression Evidence • Orientation • Show where the impression is located in the overall crime scene. • Lighting • Block out the ambient light with an umbrella and use a strong light source at an oblique angle to show the best details. • Close-up • Use a scale on the same plane as the impression. • Keep the film plane 90° to the impression • Consider using a tripod
Tire Impressions • Photograph tire impressions in sections showing one circumference of the tire. • Taking overlapping photographs, with a tape measure, parallel to the tire impression. • Keep the film plane 90° to the impression
Photography of Bloodstains • Use color film • Take orientation photos to show location • Take close-up photos to show detail • Keep the film plane 90° to the print • L-shape ruler is preferred to get both width and length of stain • Consider using a tripod
Photography of Bloodstains • Use bounced lighting or diffused light. • Oblique lighting works best when dealing with stains on fabric (very low angles). • May need additional magnification • A macro lens or the macro feature on the camera • A step-up lens
