Unit 3: Prints
3.1 Fingerprints: History, Importance, Classification
The history: the ancient use (the clay impressions); the 19th-century science (the Galton-and-Henry systems — the classification’s birth; the first forensic identifications’ era). The importance: the individuality (no two persons’ prints identical — the biology’s ridge patterns fixed before birth); the permanence (the lifetime’s constancy); the economy (the cheap, the rapid, the recordable — the databases’ world). The classification (the exam’s core): the three fundamental patterns — the arch (the plain-and-tented), the loop (the ulnar-and-radial — the core-and-delta’s counting), the whorl (the plain, central-pocket, double-loop, accidental); the Henry classification’s filing logic (the primary-and-secondary divisions — the ten-print card’s world); the modern AFIS/ABIS (the automated searching — the database’s identification in minutes).
3.2 Lifting and Examination of Fingerprints
The scene’s prints: the patent (the visible — the inked, the bloody), the latent (the invisible — the skin’s oils-and-sweat), the plastic (the 3D — the wax, the putty). The visualisation’s methods: the powder dusting (the black-and-magnetic), the chemical developers (the ninhydrin for the porous — the paper; the cyanoacrylate fuming — the superglue’s polymerisation), the light-based (the UV, the laser, the ALS). The lifting: the tape’s-and-gel lifters’ taking; the photography’s record. The examination: the analysis-comparison-evaluation-and-verification (the ACE-V discipline); the examiner’s conclusion (the identification, the exclusion, the inconclusive); the standards’ debates (the no-error myths, the examiner’s certification — the science’s honesty).
3.3 Features of Minutiae Pattern in Fingerprints
The minutiae — the ridge’s events: the ridge ending (the termination), the bifurcation (the split), the island (the short ridge), the dot, the spur, the crossover, the enclosure (the eye), the delta-and-core (the orientation’s landmarks). The comparison’s logic: the minutiae’s sequence-and-spatial-relationship (the points’ matching — the traditional 12/16/8-point debates among jurisdictions; the modern holistic-tendency); the examination’s record (the charted enlargements — the court’s demonstration).
This is a preview. The complete Forensic Science notes — full unit, Exam Focus box and model questions — are in the PDF / full version. Get the complete notes →