IDIAI

Documentation & Recovery of 2D Footwear Evidence

Footwear impressions can reveal, in many cases, the type, make, design and approximate or precise size of the footwear that made them.  This can be done through class and individual characteristics that are visible in the impression.  The information can often assist in identifying a suspect.  In addition, the location of footwear impressions at the scene can often help to reconstruct the crime.  The presence, characteristics and condition of the impression can assist in determining the number of suspects involved, their path through and away from the crime scene, their involvement in the crime, and the events that occurred during the crime.  Footwear impressions at crime scenes can also be used to corroborate or refute information provided by other witnesses.  This hands-on workshop is designed to help the student learn the best methods for recovering 2D footwear impression evidence.  The collection of exemplar prints will also be discussed and new technology and methods demonstrated.

Detect More Evidence: Search Beyond the Visible

Various types of evidence are often overlooked at a crime scene because they are not visible to the naked eye. When using an alternate light source with the proper corresponding filter, it is still possible to miss items of evidence due to background interference or improper angle of illumination. The purpose of this workshop will be to introduce attendees to various methods utilized in detecting evidence beyond the visible range. An introduction to light theory and techniques utilizing wavelengths of light beyond the visible range on notoriously difficult surfaces will be discussed. This will include ultraviolet and infrared examination to detect the presence of biological fluids, gunshot residue, and fingerprints on difficult backgrounds. Novel oblique lighting techniques will be explored to detect evidence on raised surfaces and footwear impressions. Bandpass filtering techniques will also be explored to aid in the detection of evidence at crime scenes. Attendees will be introduced to non-visible lighting techniques and digital capture of fingerprints developed using various treatment methods including cyanoacrylate fuming and IR fluorescent fingerprint powders.