Application of Infrared Photography for the Detection of Hidden Evidence at the Crime Scene: Passive and Active Thermography Techniques Through Drywall

• NCJ Number: 239549
• Journal: Identification Canada Volume: 35 Issue: 2 Dated: June 2012 Pages: 40-55
• Author(s): Clayton H. Asano; Dr. Tracy Rogers; Gregory McGuire; Dave Juck; John Jacobs
• Date Published: June 2012
• Length: 16 pages
• Publication Format: Article
• Publication Type: Report (Study/Research)
• Language: English
• Country: Canada

Annotation

This research determined the effectiveness of a digital IR camera (FLIR B200) to detect various items to evidentiary value behind drywall.

Abstract

Infrared (IR) cameras often utilize the principle of thermography to create an image using temperature. Forward-looking infrared (FLIR) is a non-invasive technology proposed to facilitate hidden evidence detection at the crime scene. The purpose of this research is to determine the effectiveness of a digital IR camera (FLIR B200) to detect various items to evidentiary value behind drywall. Handguns, knives, cashboxes, videotape cassettes, DVDs, and mock-marijuana drug bags were hidden in sections of a drywall unit with combinations of insulation and paint present. For each of the above, four nearly identical items were hidden inside the wall at a time and the process repeated for a total of six trials per item. The methodology was employed for two techniques: a "passive" technique with no change in energy, and an "active" technique where rapid cooling created a change in energy. The techniques detected items with a success rate of 57 percent and 91 percent, respectively. (Published Abstract)