Table of Contents:

Blue Star

Per Evident, Bluestar Forensic Blood Reagent is a blood enhancement reagent whose purpose is to reveal bloodstains that have been washed out, wiped off, or are invisible to the naked eye. This product is intended for crime scene investigators. Based upon chemiluminescence, the unique formula qualifies it as the most effective blood reagent available on the market for crime scene, as well as forensic lab use. Bluestar Forensic does not alter the DNA of the revealed blood which allows for subsequent comparison. Bluestar is non-toxic and easy to prepare and apply.

Fluorescein

Per Evident, Fluorescein causes a catalytic reaction to occur between the hemoglobin in blood and oxygen. This reaction produces a luminescent

Another technique for rinsing chemical from tape

Figure 5.52 Another technique for rinsing chemical from tape.

stain which will luminesce in the dark when excited with UV or ALS. The major advantage of Fluorescein is that it will continue to luminesce for hours under UV or ALS after the initial application, and without additional applications of the reagent. This product is commonly used to detect blood spatter, bloodstained fingerprints, and footwear impressions, as well as, blood evidence which has been concealed or cleaned.

Luminol/Bluestar: When sprayed on the suspected area, the prints will fluoresce. The challenge with this technique is that it must be undertaken in a darkened environment. Luminol prints must be photographed at the time of fluorescence because when luminol stops reacting with the blood, the prints will no longer be visible.

With all of the blood analogs, photographs should be taken immediately to record the prints. Certain items may be taken into custody,

Tape in water yielding results

Figure 5.53 Tape in water yielding results.

while other items may have to be left at the scene depending on the circumstances.

As a reminder, when deciding which method(s) to choose, always utilize sequential processing.

Sequential Processing (Guide)

  • 1. Available light (ambient light/flashlight/ALS/ultraviolet)
  • 2. Powder(s)
  • 3. DFO
  • 4. Ninhydrin
  • 5. Dye stain

Procedure after Developing Prints

1. Photograph where appropriate. The photos should be done with and without a scale. The best type of scale is the ABFO, L type of scale.

Tape yielding results

Figure 5.54 Tape yielding results.

Overalls of the item where the print was developed should be taken, as well as close-ups showing the print itself. If possible, a one-to-one photo should be taken.

  • 2. Upon completion of the photography, the decision must be made whether the entire item will be taken or whether the print will be lifted from the item. When appropriate, the entire item or object should be retained for use in court. Note: Remember, the print is the evidence, not necessarily the surface that the print was developed from.
  • 3. Where a lift is made and placed onto a latent fingerprint lift card, the following information should be present:

a. Case/report number

b. Date/time

Small Particle Reagent and wet objects

Figure 5.55 Small Particle Reagent and wet objects.

c. Scene address

d. Person making the lift

e. Type of object

f. Place of lift (Note: A sketch should be made on the card near the lift)

  • 4. Take elimination prints from victims, and witnesses where appropriate.
  • 5. Care and transportation of the evidence:

a. Ensure the chain of custody is recorded to provide accountability.

b. If items need to be secured, ensure proper securing of the item’s by top and bottom, or in a place least likely to damage the item or fingerprints.

Wet object

Figure 5.56 Wet object.

Spray Small Particle Reagent on wet object

Figure 5.57 Spray Small Particle Reagent on wet object.

Spray Small Particle Reagent on wet object

Figure 5.58 Spray Small Particle Reagent on wet object.

 
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