Vocabulary: Latent Fingerprint
When deposits of oil and/or perspiration from a finger leaves a print on a surface it is known as a latent fingerprint. These fingerprints are not always visible to the naked eye, thus requiring a dusting technique with fine powders to make it visible. Once the power is on the oil/perspiration, it can be lifted with transparent tape for analyzing, protecting, and storing. Another technique for revealing latent fingerprints is to shine a laser at it, the laser will make the print(s) glow allowing for photographs to be taken.
Image Source: Daekow. Fingerprint-magnabrush. Wikimedia Commons.
Aluminium is the most common powder used to develop latent fingerprints. A magna brush is a great tool for applying magnetic-sensitive powders over a hard surface. The aluminium adheres to the residue left behind by the oil/perspiration of a finger/hand, and reveals the print(s).
Image Source: National Institute of Standards and Technology (NIST). Latent Fingerprints (6774265822). Wikimedia Commons.
Fingerprints have been used for various purposes throughout human history. Thumb prints were used on clay seals in ancient China, and the ancient Babylonians used fingerprints on clay tablets for transactions.
Image Source: Mississippi Department of Archives and History. 6.13, 1963. Rifle that killed Medgar Evers. Located latent fingerprints on telescopic site. Medgar was shot off Delta Drive, Jackson, Miss. Wikimedia Commons.
Medgar Wiley Evers was an African American civil rights activist in Mississippi, and a World War Two veteran. On June 12, 1963, Medgar was assassinated by Byron De La Beckwith a member of the White Citizens’ Council, that was formed in Mississippi to resist the integration of schools, and civil rights activism. Medgar Wiley Evers was laid to rest with full military honors at Arlington National Cemetery. In the 1960s, the all-white juries failed to reach verdicts for the first two trials of Beckwith causing civil rights protests over the murder of Evers, and its trials. In 1994, new evidence in a new state trial led to Beckwith’s conviction
