Latent Print Derivatives

They first had to identify whether the body was indeed Tiernan’s or not and two days after the body was found, fingerprinting methods indeed determined that the body was Leanne Tiernan. Despite her body being found 9 months later, her body was still intact enough to gather fingerprints. Fingerprinting proves to be a critical method in forensic cases as no two individuals have been recorded having the same fingerprint, making it an ideal way to identify suspects or victims. Fingerprints are also individual characteristics making it nearly 100% chance that it could be traced back to a source. Getting something Tiernan may have touched can then be compared to a fingerprint(s) taken from her body. Fingerprints have ridge characteristics known as minutiae and can also be classified on their general pattern known as loops, arches, and whorls. Fingerprints also do not change unless damage is done to the dermal papillae, which makes fingerprints a powerful use of evidence. Extracting a fingerprint from Tiernan would require pressing a finger into an ink pad and then transferring the impression onto a card that would be examined by a professional. However, getting a sample to compare her fingerprint would require investigators to find a latent fingerprint (prints that are left on a surface which are invisible to the naked eye) of Tiernan. When we touch something, we leave impressions on surfaces due to the sweat and oil and as long as the

One of the most important purposes of physical evidence is to establish the identity of a suspect or victim. Some of the most valuable clues at a crime scene are fingerprints. "Processing a crime scene" is a long, tedious process that involves focused documentation of the conditions at the scene and the collection of any physical evidence that could possibly shed light on what happened and point to who did it.

Latent fingerprints found at crime sights or else developed in the laboratory are categorized by examiners as patent, latent, or plastic impressions1. The word latent means hidden or unseen. Latent prints are undetectable until brought out with a physical, chemical and fuming process. The physical developer is a means to detect fingerprints on dry and wet, including paper articles, clay-based products and adhesive tapes. Ninhydrin is one of the most widely used chemical reagents for enhancement of latent finger print impressions on porous substrates. Nonporous surfaces do not absorb. These surfaces repel moisture and often appear polished. They include glass, metal, plastics, lacquered or painted wood, and rubber. Superglue (cyanoacrylate) fuming is the best example for such non-porous substrate analysis.

In quadrants 1 and 2 how the amount and constituents of the fingerprint residue on the substrate affects the fingerprint image, is determined. In quadrant 1, excess sebum and moisture is first removed from the finger tips with the help of a clean cloth. In quadrant 2, fingertip is first wiped around the nose or forehead to create excess sebum. Quadrant 3 and 4 were used to compare the details between untreated and dusted fingerprint residues.

Minutia points represent positions where friction ridges end abruptly or where a ridge branches into two or many more ridges. A typical good-quality fingerprint template contains 20-70 minutiae points; the actual number depends on the size of the finger sensor surface and how the user places his or her finger on the sensor. The system stores the minutiae information position and direction along with the user's demographic information as a template in the enrollment database.

In conclusion the relationship between the properties of skin and friction skin impressions is that without these characteristics or capabilities fingerprints wouldn’t exist. The

Explain the principles and processes used in the analysis, comparison, evaluation, and verification of latent fingerprints. Latent prints are formed when the body’s natural oils and sweat on the skin are deposited onto another surface. Latent prints can be found on a variety of surface they are not readily visible and detection often requires the use of fingerprint powders, chemical reagents or alternate light sources. Generally speaking, the smoother and less porous a surface is, the greater the potential that any latent prints present can be found and developed. Investigators often perform cyanoacrylate processing, or fuming, of a surface before applying powders or dye stains. This process, typically performed on non-porous surfaces, involves exposing the object to cyanoacrylate vapors. The vapors will adhere to any prints present on the object allowing them to be viewed with oblique ambient light or a white light source. (Latent, n.d)

Word choice is perhaps one of the most important aspects of writing in the forensic science discipline. “Fingerprint examiners often argue that because friction ridge formation is induced by the stresses and strains experienced by the foetus in utero, which are random and infinite, it is likely that they subsequently produce a random, infinite variety of friction ridge patterns.” (Page, 2011). In the forensic science discipline, there are keywords that have to be known to have a professional and scientific style of writing the will be acceptable. A forensic scientist cannot write a report about the fingerprints of a subject and say that the has a unique pattern of bumps on their fingers. They have to use keywords such as friction ridge patterns, for their report to

Latent fingerprints are mostly impressions left at a scene that are not noticeable to the naked eye; they are also one of three classifications of fingerprints that can be found at the scene of a crime or anywhere else. Latent prints

Fingerprints can be taken from a crime scene in various methods. Fingerprints are classified into three categories depending on the surface they are found. Fingerprints on soft surfaces are most likely to be three-dimensional plastic prints such as soap, wax, wet paint, fresh caulk, etc. (“A Simplified Guide To Fingerprint Analysis”, n.d). The fingerprints on hard surfaces are patent or latent prints including blood, dirt, ink, paint, etc. transferred from a finger or thumb to a surface (“A Simplified Guide To Fingerprint Analysis”, n.d). Patent prints can be collected using photography. The prints are photographed in high resolution with a forensic measurement scale for the image for reference. There are multiple methods for discovering and collecting latent prints. Alternate Light Source (ALS) use

Though Hershel, Faulds, Galton and others set the stage in methods to indicate fingerprints should have been used for identification there was still controversy around the science. With the advances of technology, we now have a better understanding of why fingerprints have only been identified to a single individual. They are unique and permanent. Embryology finds six weeks in utero formations of early notching for what will become fingers starts. By week seven, webbing of the finger is almost gone and volar pads start to form. During week ten through twelve, initial formation of epidermal ridges begin. Primary ridges begin at the apex of the volar pads, tip of the finger and just above the first joint. Secondary ridges start to form by week sixteen and stop the formation of primary ridges. By twenty-four weeks ridge formation has completely finished. For over one hundred years friction ridge impressions have been only known to relate back to only one source thus resulting its broad usage in law enforcement, banking, government buildings for identification purposes and etc.

Latent print work in cases involving such cases, for example, murder cases is one of the processes that is used by the investigators of a crime in the course of trying to unravel the culprits that were involved in the murder. In cases where the identity of the victim is not clear or is not determined immediately, latent impressions could also be used to bring to light the identity of the victim. Latent impression about forensic science could be defined as any accidental or chance impressions that might have been left as a result of friction ridge skin on something like a surface. The impressions that have been left could be visible or sometimes invisible during the time that they are deposited on the surfaces although the word latent is used to refer to invincible. The skin contains some deposits of oil as well as perspiration that is responsible for coating the surface.

“Fingerprint recognition is one of the divorce inference using the impressions made by the minute ridge formations or patterns found on the fingertips. No two people have exactly the same arrangement of the ridge patterns, and the remaining patterns of any one individual unchanged. Fingerprints infallible provide a means of personal identification. Other personal characteristics may change, but not fingerprints”. (1)

The purpose of this experiment was to determine how different surface temperatures affect the appearance of latent finger prints. In order to run this experiment, thirty Standard Select Carolina Microscope Slides were wiped with rinsed with tap water then blotted dry with Kimwipes. Ten microscope slides were chilled to negative nineteen degrees Celsius, ten others were left out, resulting in a temperature of twenty-three degrees Celsius, and another ten were incubated to thirty-seven degrees Celsius. After five minutes the slides were removed from the freezer and a thumb print, using Alex’s left thumb, was placed on each slide. Alex’s thumb was used as a general representation of the public, as while no fingerprints can be the exact same;

Capacitive sensors use an array capacitor plates to image the fingerprint. Skin is conductive enough to provide a capacitive coupling with an individual capacitive element on the array. Ridges, being closer to the detector, have a higher capacitance and valleys have a lower capacitance. Some capacitive sensors apply a small voltage to the finger to enhance the signal and create better image contrast.