Latent Print Collection
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- Published: Wednesday, 30 March 2022 20:28
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The intention behind the guidance given by the MABRC on latent print collection is not to train researchers to be latent print examiners, nor to be crime scene investigators. Rather the guidance provided here is to give researchers a means of using makeshift equipment and proper protocols in the effort to successfully collect latent prints of suspected Sasquatch should the opportunity present itself.
Researchers should be aware that it is difficult at best, to substitute for professional fingerprint equipment, however the technique and guidance provided here can successfully lift latent prints under good conditions.
The list of supplies that a researcher will need a very simple and inexpensive.
-- A small, empty squeeze bottle (similar to an eye drop bottle, preferably with a screw off top)
-- A bright flashlight
-- A two inch wide roll of clear tape
-- A black or dark colored plastic sheet (transparency sheets work perfectly)
-- A fine powder such as talc or cake flour
-- A camera lens brush with fine hair at one end, and a bulb at the other end (similar to a mini turkey boaster)
Researchers should be aware that the probability of encountering a Sasquatch print that is suitable to be lifted is minimal, and more than likely will either be encountered on a window, vehicle surface, or other nonporous surfaces. Prints will most readily be apparent after the surface has been coated in a fine dust, such as a vehicle that was used in field research.
Researchers should follow the following protocol in order to minimize contaminating the print, and aid in the successful recovery of the observed sample.
1. Photograph the print or hand mark of the surface prior to conducting any attempt at recovery. The use of a photographic scale or other measuring device is vital in the attempt to document the print.
2. If the print is difficult to see, attempt to use the flashlight at different angles in order to highlight the print for photographing. Dependent upon the camera the researcher uses, a flash may or may not be needed.
3. Take several photos from various angles and distances.
4. Annotate in your research journal what the photo is of. (The researcher may need to describe what is in the photo for later recollection.)
5. The researcher should now put on a pair of powder free latex or nitrile gloves in order to prevent contaminating the print, or worse yet, leaving one of his/her own, and lifting it as the specimen.
6. The small squeeze bottle should be filled approximately one-third to one-half full of the fine powder. It is imperative that the bottle be capped after every use in order to prevent moisture from absorbing into the powder and making it difficult to use. (A cheap trick to prevent moisture from sticking the powder together is to add a little dry, white rice to bottle)
7. Firmly shake the bottle a few times in order create a dust within the bottle, then remove the cap and softly squeeze the bottle away from the suspected print.
8. Pay attention to how much dust comes out of the bottle when squeezed, and at what direction the air is carrying the dust. Seldom is the air completely still, so pay attention to the direction it flows, and how fast it settles.
9. Once you have determined the air flow direction, the rate of descent of the dust, and how much dust exits the bottle with each squeeze, move to the opposite side of the print from which the air is flowing.
10. Softly squeeze the bottle and attempt to drift the dust onto the print. The key here is to lightly dust the print with powder, but not so much that the surface is obscured. (This is something that you can practice with at home before going to the field)
(If more powder is needed to dust the print, ensure that you continue to shake the bottle before squeezing it)
11. Using the lens brush, softly squeeze the bulb in order to blow air out the brush, and blow away any excess powder. Ensure that the brush DOES NOT touch the print at this point.
12. Use the flashlight from various angles to check and see if a print is visible under the powder.
13. If a print is apparent, but not clear, delicately use just the tip of the brush and softly brush it across the print to further remove any excess powder. Extreme care should be used on this step as it is very easy to destroy a print using the brush.
14. Using the roll of tape, start the tape and double back the end in order to make it easier to remove later.
15. Tack the beginning edge of the tape approximately two inches past the print, and with one hand controlling the tape roll, use the other hand to secure the tape to the surface.
16. Using one finger, slide it down the non-adhesive side of the tape, securing it to the surface and the roll of tape is maintained taut using the other hand. It is vital that the tape not have any kink, wrinkles, or air bubbles under it as it is secured to the surface.
17. Once the tape has been secured successfully two inches past the print, cut the tape and secure the end to the surface.
18. Using the transparency, or other similar dark material, cut a piece that is approximately one inch larger on all sides than the print that is attempting to be lifted.
19. If using a transparency that has been printed on, ensure to use the opposite side which will be shiny and non-porous. It should be noted that paper does not serve as a good medium when using this method.
20. Place the “card” near the tape and use the fingers of one hand to secure the flat end of the tape to the surface.
Using the other hand, grasp the doubled tag of tape and slowly begin to peel it from the surface. Ensure that the tape is peeled back smoothly, firmly, and evenly as it is very easy to ruin a print at this point.
21. Once the tape has been removed and is secured using both hands, tack the flat end of the tape back to the surface and to one end of the “card” simultaneously.
22. Using one hand to control the tape, use one finger of the other hand to firmly slide against the non-adhesive side of the tape working your way up the card. Ensure that the tape is secured to the card smoothly, evenly and firmly. Kinks, wrinkles, or air bubbles can destroy the print.
23. Once the tape is completely secured to the “card”, remove it from the surface and trim any excess tape from all four sides.
24. Using a label, place it on the back of the card and label it with the appropriate tag number. Once this is done, fill out the specimen collection form and label it with the tag number from the print, and add this tag number to your research journal entry.
The researcher should be aware that usually a print is not able to be lifted again, once it has been compromised by the tape. Additionally, if there is more than one print lifted from the same location, each print will receive a different tag number, however only one specimen collection form is needed, but do include all the tag numbers from all samples on that form. All tag numbers should also be entered into your journal entry.