October 2001 Volume 82 Number 10 "serving the protectors"
Latent Prints in Dust
By Captain Curtis C Frame Criminal Investigation Division Jasper County Sheriff’s Office, Texas, USA

A latent print found in dust may be the only clue in which there are no other leads. And, because the areas that are routinely touched by the victims are not normally dusty, the dust print we find may be the only link we have of the perpetrator to the crime scene. However, most crime scene and latent print examiner experts will say that, regardless of their importance, latent prints in dust are a nightmare. This is due to the fact that a latent print in dust was actually left there due to the dust being removed by adhering to the ridges of the skin that touched it.

So, in order to avoid having to reverse the negatives or use a liquid lifter, I’ve been working with my colleague in hopes of finding an easier, simpler method of obtaining these extremely important latents. And, after a lot of time, effort, and countless experiments, I think we’ve found a solution.

To remove a latent print in dust, simply place a clear piece of wide fingerprint tape over the print, and apply with very slight pressure. After lifting the tape from the surface, you can hold the tape in front of a light source and see the lifted latent dust print. (The friction skin ridges will not be seen as well as the friction skin furrows. The dark lines that you see will be the dust not taken from the surface by the friction skin ridges, but that which was left behind by the friction skin furrows.) Then you will place the tape (sticky side down) over the top of an ordinary styrofoam cup. Because you have used the wide tape, the print will be sealed and well preserved, without fear of damage or contamination, inside the styrofoam cup.

The remaining process is also relatively simple. When you are ready to proceed with the examination of the print that you lifted, simply cut the bottom of the styrofoam cup off and discard. Then place a black card or black sheet of construction paper, on the bottom of the upper half of the styrofoam cup. This will create a black background for your print. Now place under a camera with direct lighting. The inside of the white styrofoam cup will create bounce lighting, which will help to balance the light for your photograph. You may need to “play” with the lighting and/or the exposure, just as you would any other latent photography, in order to achieve the best picture.

By using black and white film, and black background, the pictures, when developed, will produce a latent dust print with the black lines being a representation of the friction skin ridges. The white lines of the print will be due to the dust that was left by the friction skin furrows being adhered to the fingerprint tape. Again, the photograph of the latent dust print, using this method, will show black ridges and white furrows.

After you have finished photographing your latent dust print, simply preserve the print by placing it (cup and all) inside another styrofoam cup, and seal with tape.

Be very careful when lifting a latent dust print from its surface. There is no such thing as a “second” lift. You may want to practice on a latent dust print of your own, in order to achieve the best pressure of tape application, as well as the best picture, when you photograph your print in the styrofoam cup.

About the author

An experienced crime scene investigator, Curtis C Frame has worked on countless murder cases, including the highly publicized dragging death of James Byrd, Jr. He specializes in fingerprint comparison and bloodstain/spatter analysis.

He had, on occasion, found fingerprints in dust that could not be easily lifted for comparison purposes. In light of the prints’ importance, he began to work on a technique that would allow for their quick, easy collection and comparison.

The technique that Frame and one of his colleagues developed has been taught in law enforcement schools throughout Texas and at the FBI academy in Quantico, Virginia.

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