Print Positioning Does Make a Difference
Written by Hayden B. Baldwin   

Fingerprints have long been considered one of the most reliable types of evidence. Fingerprint identification can place a suspect at the scene of a crime, but is this enough for a conviction in every case? The position, direction, and location of the print in a crime scene can help solve the case.


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Making note of a fingerprint's position, direction, and location at the scene can help an investigator piece together important bits of information.
 
Consider these examples:
 
Many of us have patronized a supermarket, service station, or other type of business that was later burglarized. It is possible that our prints could be found on doors, counters, and other places with public access. In such situations, prints are of little value unless they can be located on a moneybox under a counter, in the manager’s office, or in other areas not available to the public.
 
A plate-glass window that was broken to gain entry could have been touched by anyone at some time. Print positioning has now become a factor. A burglar may have removed pieces of broken glass from the frame to enlarge the opening. A thumbprint and an index fingerprint on opposite sides of the glass are unusual findings. This positioning would be hard to achieve with the window intact.
 
Let’s consider a residential burglary in which the suspect has been a frequent visitor to the home. This fact may not be known at the time the scene is processed and the fingerprints recorded. Therefore, it is necessary to record the location and the direction of the print. The print may be located on an object a visitor could not have touched before. However, a visitor’s print found on a window sill at the point of entry could have been left during a visit when he or she leaned on the sill to look out the window. If the lifts are properly marked, the direction will be recorded and may be consistent with climbing in the window rather than looking out from the inside.
 
Consider a case where a wife reports that her husband was killed when the shotgun he was cleaning accidentally discharged. Crime scene investigators may find the husband’s and wife’s fingerprints anywhere in their home. However, the wife’s prints in a normal firing position on the forearm and stock of the gun, the absence of any gun cleaning materials, and a range determination that does not fit with her explanation could mean the difference between an accidental death and murder.
 

Marking a lift card with an arrow helps orientate the examiner so it is known which direction is "up" (on a vertical surface) or "away" (on a horizontal surface).
 
When marking a lift card for identification, an arrow should be placed on the card to identify what direction is up or what direction is away from examiner. These marks will help identify the position of the print when lifted. If photographing the print before lifting, then in addition to a scale and an ID tag to identify the print, include an arrow on the tag to identify the position of the print.
 
A crime scene investigator must think beyond simply finding fingerprints and consider what they may mean based on their location, direction, and position. These findings also may lead an investigator to check for other types of evidence that could confirm his evaluation of the scene.

About the Author
 
Hayden Baldwin is the Executive Director of the International Crime Scene Investigators Association (ICSIA). He has more than 18 years experience in crime scene investigations, the last 11 years as the supervisor. He retired as a Master Sergeant with the Illinois State Police in 1998. For decades, he has shared his expertise through instruction at universities, colleges, and police academies, including the FBI Academy, and is the lead instructor and program developer for the Crime Scene Technician Program for the Criminal Justice Institute in Little Rock, Ark.
 
Note: This article was provided by the International Crime Scene Investigators Association (ICSIA). www.icsia.org
 
 
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