Latent Print Examiner

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.

Other professional opportunities offered by Forensic Science is that one may join a Professional Association involving their career. For example, the American Academy of Forensic Science (AAFS) is a Professional Association that aims to promote professionalism, integrity, competency, education, foster research, improve practice, and encourage collaboration in the forensic sciences. Like any job, personal opportunities would encompass things like making friends with co-workers, self satisfaction in one’s work, and other things of the sort.

Studying forensic science, I have learned the need to work in an organised fashion and keep accurate records of the task being completed. These are qualities that will stand me a good stead. In testing biological samples such as blood, or analysing fingerprints I have gained an insight of the need for careful observation and the need to identify samples carefully. Analytical chemistry has given me experience in practically showing ability to interpret results and reach conclusions. Studying

For over a century fingerprints have been one of the most used tools of forensic science. Fingerprints have been used to identify criminals of small crimes

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

That is a good question, one worth answering. Forensics is a scientific tool that has come to its own starting about the 80’s. Fingerprinting was one of the first techniques used to help in identifying the criminals that committed the heinous acts. Fingerprinting uses a brush and powder to enhance the ridge details on the fingertips adhering to the oils left behind. Another awesome way they have been able to pull prints off soft surfaces like bed sheets is by using superglue and heat. Fascinating isn’t it? Since then Forensics has become even more evolved. Fingerprints now go into a database known as AFIS or Automated Fingerprint Identification System, which has the prints of everyone

In this example, the fingerprints are found on a piece of paper. First you spray the fingerprint with the ninhydrin solution and allow it to dry for a few minutes. After it dries, two sheets of paper towels are placed on the bottom of the sheet of paper and two sheets of paper towels are placed on top. A clothing iron is used to apply heat to the paper towel — the heat and moistness develop the fingerprints. You continuously check the fingerprints to see if they are developed enough and once they are, the fingerprints are placed under an extremely strong light and examined with a magnifier or an image is take of the prints and sent to the lab. Furthermore, spraying the print with acetone after the ninhydrin process can develop more detail from the fingerprint. (Forensics Lab 8.3: Revealing Latent Fingerprints Using Ninhydrin, n.d.) These latent prints need to be fingerprinted as soon as they are developed as latent fingerprints and known to fade. (Wertheim,

of Forensics. What interest me the most about this job was my mom by her being in the

The main provision in all cases is the avoidance of including fingerprints to evidence, or of ruining the ones already existing at the time. Once the crime scene has been carefully recorded and each of the evidence located have been annotated, then the process of gathering and analyzing can commence. The crime scene investigator will start by collecting the most delicate and easily prone to be lost evidence. Locating latent fingerprints at the crime scene requires use of techniques that makes it ideal for visibility. Investigators will use a several of methods to visualize the print, however it will depend on the surface that print is being lifted from. All non-movable and fixed items at a crime scene sustained to be handled on the scene using one of

The amount of information that can be obtained through someone’s hands is astounding. One can determine the years of scarring from hard work, or the blisters from misuse. The most information can be obtained at the very tips of fingers, and what they leave behind. Fingerprints supply great evidence to help identify who was there, and possibly how many people were there. However, the problem becomes that there are too many prints found at one scene. It is difficult to try and determine when they were made based on physical appearance and common techniques. Nowadays, the age determination of latent prints can be achieved with a new approach using the sweaty residue of latent prints, and a small electrical charge.

Latent impressions are often found on smooth surfaces. The onsite processing for latent prints shall involve an examination of the body of the deceased, walls, counters and floor. UV light should be used to identify biological stains such as sweat, blood and saliva that may have been deposited on the counter, floor or on the deceased’s body (Siegel, Knupfer, & Saukko, 2013).

Even with the advanced state of forensic sciences some surfaces and circumstances prove difficult to successfully lift, or even detect, fingerprints from. There are now several methods of enhancing latent fingerprints for collection. These methods use chemicals, light sources and other techniques to enhance latent ridge marks on materials that prove difficult to successfully identify and lift prints from. These surfaces include certain types of metals, porous surfaces, and certain kinds of paper. We will discuss three types of latent finger print enhancement that are relatively new or still in the beginning stages of testing, two chemical, elctrochromism and yellow

The variety of foreign materials that might be found in a latent fingerprint deposit is virtually unlimited. The actual composition evidently depends on what the person has handled prior to the deposit of the impression. While it would be impossible to list them all, a few of the more likely materials include:

[7]. An inked thumb mark was scanned with a scanner. The empty spaces between the ridges of the scanned image were converted into a transparent format by processing a scanned image of the fingermark using Adobe Photoshop and used as the digital master fingermark. The master fingermark was printed with an inkjet printer installing an inkjet cartridge case filled with artificial sweat solution. Table 2 shows the formulation of artificial sweat solution. The printing intensities of the artificial latent fingermarks were adjusted with [output levels] Photoshop functions (latent fingermark printing intensity decreases as the output level increase). The intensity of the artificial latent fingermark printed on the small pieces (8–12 cm) of photocopy paper was estimated by the weight difference of the paper before and after the printing. The printing and weighing process was repeated 5 times, and the weight changes of paper are shown in Fig. 1, indicating that the intensities of printed artificial latent fingermarks are almost linearly decreasing as the output level of printing increases. Since the printer performance may change over time, the quality of the printed image may change depending on the time, even if one image is printed with the same printer. Therefore, the printing quality of latent fingermark was confirmed by observing the weight change in the paper immediately

The most significant milestone in forensic science is the use of fingerprints in business transactions. People in accident Babylon used fingerprints because they are unique to every human being. The reason fingerprints are distinct to individuals is because they are formed when the bottom layer of the epidermis develops at the different rate than the rest of the skin, thus it buckles and tugs on the