The Science Behind Forensic Microscopy: Standards for Use

Microscopy

Microscopy is the art and science of creating, recording, and interpreting magnified images. Forensic Microscopists have a diverse knowledge base in materials and specialized skills of visual literacy.

Forensic Microscopy

The application of the microscope to perform microscopical examination of physical evidence by making detailed observations, measurements, and  recordings of microscopic trace (transfer) evidence to assist the trier of fact in the resolution of contentious legal issues, civil or criminal.

Background

The compound microscope dates back to latter half of the 16th century.  Its invention is shrouded in mystery.  There are many claims to the title “Father of Microscopy” but the extensive amount of work  by many innovators of that era and the lack of adequate documentary evidence shrouds any claims.

The word microscope was coined by Giovanni Faber on April 13, 1625.  Its meaning was the same then as is today; an optical instrument capable of producing a magnified image of a small object.  However, today, electromagnetic radiation other than light may be used for illumination.

The word microscope was coined by Giovanni Faber on April 13, 1625.  Its meaning was the same then as is today; an optical instrument capable of producing a magnified image of a small object.  However, today, electromagnetic radiation other than light may be used for illumination.

Robert Hooke (1635-1703), at the request of King Charles II, assembled his extensive works of microscopical observations and reports to the Royal Society in a book titled Micrographia.  The original was published in 1665.

Anton van Leeuwenhoek (1632-1723) made and used microscopes constructed of a very small, high-powered, single lens.  These small hand-held microscopes were (are) can resolve 1.4 micrometers at 270x magnification.

Hans Gustav Adolf Gross

Guide for Forensic Investigators as a System of Criminalistics, (1891) Handbook for Magistrates, Police Officials, Military Policemen, (1893)

(1847 – 1915) In 1912, he founded the Institute of Criminalistics at the University of Graz’ Law School.

International Academy of Criminalistics

1929 – Left to Right:  Prof. Marco Bischoff (Swiss), Prof. Siegfried Turkel (Austrian), Prof. Christian Jacob van Lodden Hyulsebosh (Dutch), Prof. Georg Popp (German), and Prof. Edmond Locard (French).

Edmond Locard

1877 – 1966

Locard’s Exchange Principle: “it is impossible for a criminal to act, especially considering the intensity of a crime, without leaving traces of his presence”……the perpetrator of a crime will bring something into the crime scene and leave with something from it.

“Whenever two objects come into contact there is always a transfer of material.”

In 1910, Locard convinced the Police Department of Lyon to give him two attic rooms and two assistants, to start what became the first police laboratory.

Locard, Edmond, “Dust and Its Analysis: An Aid to Criminal Investigation, The Police Journal, Vol. 1, No. 2 (1928), pp.177-192
Locard, Edmond, “The Analysis of Dust Traces. Part I”, The American Journal of Police Science, Vol. 1, No. 3 (1930), pp. 276-298
Locard, Edmond, “The Analysis of Dust Traces. Part II”, The American Journal of Police Science, Vol. 1, No. 4 (1930), pp. 401-418
Locard, Edmond, “The Analysis of Dust Traces. Part III”, The American Journal of Police Science, Vol. 1, No. 5 (1930), pp. 496-514

Paul Leland Kirk

Crime Investigation (1953):

“Wherever he steps, whatever he touches, whatever he leaves, even unconsciously, will serve as a silent witness against him. Not only his fingerprints or his footprints, but his hair, the fibers from his clothes, the glass he breaks, the tool mark he leaves, the paint he scratches, the blood or semen he deposits or collects. All of these and more, bear mute witness against him. This is evidence that does not forget. It is not confused by the excitement of the moment. It is not absent because human witnesses are. It is factual evidence. Physical evidence cannot be wrong, it cannot perjure itself, it cannot be wholly absent. Only human failure to find it, study and understand it, can diminish its value.”

Guidelines

Opinion of the United State District Court for the Eastern District of Pennsylvania on July 20, 1964, “ASTM is the first source to which federal, state, and municipal governments turn in seeking specifications, and ASTM specifications are more widely used by them than the specifications of any other body. “

367 ASTM documents

Guidelines

ASTM E175 – 10
Standard Terminology of Microscopy

ASTM E2228 – 10
Standard Guide for Microscopic Examination of Textile Fibers

ASTM E2809 – 13
Standard Guide for Using Scanning Electron Microscopy/X-Ray Spectrometry in Forensic Paint Examinations

ASTM E1588-16a
Standard Practice for GSR Analysis by SEM/EDS

ASTM E1967-11a
Standard Test Method for the Automated Determination of Refractive Index of Glass Samples Using the Oil Immersion Method and a Phase Contrast Microscope

ASTM E1969-11
Standard Guide for Microcrystal Testing in the Forensic Analysis of Methamphetamine and Amphetamine

ASTM E2125-11
Standard Guide for Microcrystal Testing in the Forensic Analysis of Phencyclidine and Its Analogues

ASTM E2808-11
Standard Guide for Microspectrophotometry and Color Measurements in Forensic Paint Analysis

ASTM E2809-13
Standard Guide for Using Scanning Electron Microscopy/X-ray Spectrometry in Forensic Paint Examinations

ASTM E1951 – 12
Standard Guide for Calibrating Reticles and Light Microscope Magnifications

ASTM D7690 – 11
Standard Practice for Microscopic Characterization of Particles from In-Service Lubricants by Analytical Ferrography

ASTM D6602 – 03b
Standard Practice for Sampling and Testing of Possible Carbon Black Fugitive Emissions or Other Environmental Particulate, or Both

ASTM E1968-11
Standard Guide for Microcrystal Testing in the Forensic Analysis of Cocaine

Microscopy and Microanalysis

Defect in Parenteral Vial

Particle in Solvent

Electronic Contact Failure

Metallic Particles

Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy

Polymeric Particle

Heat Sealed Packaging

Polarized Light Microscopy

Fibrous Material in Beverage

2018-08-23T20:09:23+00:00
Menu