ASTM E444-98
(Guide)Standard Guide for Scope of Work Relating to Forensic Document Examiners
Standard Guide for Scope of Work Relating to Forensic Document Examiners
SCOPE
1.1 This description covers in general the duties of forensic document examiners, also referred to as questioned document examiners, examiners of questioned documents, document examiners, or document analysts.
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:E444–98
Standard Descriptions of
Scope of Work Relating to Forensic Document Examiners
This standard is issued under the fixed designation E 444; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope 3.2.1.3 the identification or elimination of ink, paper, and
writing instruments,
1.1 This description covers in general the duties of forensic
3.2.1.4 the establishment of the date, source, history, se-
document examiners, also referred to as questioned document
quence of preparation, alterations or additions to documents,
examiners, examiners of questioned documents, document
and relationships of documents.
examiners, or document analysts.
3.2.2 Other problems are the decipherment and sometimes
2. Job Description
the restoration, or both, of obscured, deleted, or damaged parts
of documents.
2.1 The forensic document examiner makes scientific ex-
3.2.3 The work often includes a study of the information
aminations, comparisons, and analyses of documents in order
carried by a document for discovery of evidence of spurious-
to: (1) establish genuineness or nongenuineness, or to expose
ness, identification of persons, or to show significant relation-
forgery, or to reveal alterations, additions, or deletions, (2)
ships.
identify or eliminate persons as the source of handwriting, (3)
3.2.4 Document examination also includes the recognition
identify or eliminate the source of typewriting or other impres-
and preservation of other relevant physical evidence that may
sion, marks, or relative evidence, and (4) write reports or give
be present on documents.
testimony, when needed, to aid the users of the examiner’s
3.3 Equipment used in forensic document examination in-
services in understanding the examiner’s findings.
cludes: microscopes and other optical aids; photographic and
3. General Duties
other imaging devices, a wide variety of imaging materials
adaptable for use with a variety of lighting methods, including
3.1 Examiners in this field are sometimes known by the
those involving radiant energy in the ultraviolet, visible,
term “handwriting experts.” Forensic document examination
infrared, and other regions of the electromagnetic spectrum; as
includes expertise in handwriting identification. Handwriting
well as electrostatic or other devices for the detection, or
includes cursive or script style writing, handprinting, signa-
visualization, or both of indentations and other features present
tures, numerals, and other written marks or signs. Forensic
in or on paper or simular substrata. Other analytical instrumen-
document examination does not involve the employment of
tation may be used where appropriate.
calligraphic or engrossing skills, nor does it involve a study of
...
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SIGNIFICANCE AND USE
4.1 This practice separately outlines criteria and implementation approaches for the training, continuing education, and professional development of forensic science practitioners. The use of this practice can help establish training programs designed to achieve competency in targeted disciplines. The standard also describes measures to maintain competency through continuing education/professional development.
4.2 This practice provides a framework for extending learning opportunities to promote and achieve higher standards of professional practice in forensic science.
4.3 This practice is not intended to be inclusive of all possible options nor to address the challenges of a particular discipline.
4.3.1 This practice does not address proficiency testing programs or specific requirements of professional certification and licensure bodies, although the foundational requirements addressed may be essential elements for such programs.
4.3.2 This practice is not intended to supersede requirements from professional certification and licensure bodies.
4.3.2.1 Licensing and certifying bodies in a number of fields typically impose continuing education and professional development requirements on their license or certificate holders. Such requirements are intended to encourage professionals to expand their knowledge base and keep abreast of new developments. Depending on the field, these requirements might be satisfied through internal training; completion of college, university, or extension coursework; or through attendance at conferences and seminars. Individuals in such positions should obtain and document their on-going training and development as required by their licensing or certifying body.
SCOPE
1.1 This practice provides foundational requirements for the training, continuing education, and professional development of forensic science practitioners to include training criteria toward competency, documentation, implementation of training, and continuous professional development. This information is intended for forensic science service providers to help establish a training framework with program structure and content; for forensic science practitioners as they acquire and maintain their knowledge, skills, and abilities (KSAs); for subject matter experts when developing discipline specific training practices; and for training programs to manage and support the continuous development of their employees.
1.2 This practice outlines minimum training criteria and provides general information, approaches, and resources for all disciplines. The standard would complement additional specific requirements for each forensic science discipline (for example, relevant degree programs, higher education) if developed by subject matter experts in their respective fields. Discipline specific training programs should address the content and means for developing and testing competency for each applicable topic identified in Practice E2917.
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
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SIGNIFICANCE AND USE
5.1 This test method is useful for the determination of elemental concentrations in the range of approximately 0.1 µgg-1 to 10 percent (%) (See Table X1.1) in soda-lime glass samples (7 and 8). A standard test method can aid in the interchange of data between laboratories and in the creation and use of glass databases.
5.2 The determination of elemental concentrations in glass provides high discriminating value in the forensic comparison of glass fragments.
5.3 This test method produces minimal destruction of the sample. Microscopic craters of 50 µm to 100 µm in diameter by 80 µm to 150 µm deep are left in the glass fragment after analysis. The mass removed per replicate is approximately 0.4 µg to 3 µg (6).
5.4 Appropriate sampling techniques shall be used to account for natural heterogeneity of the materials at a microscopic scale.
5.5 The precision, bias, and limits of detection of the method (for each element measured) shall be established during validation of the method. The measurement uncertainty of any concentration value used for a comparison shall be recorded with the concentration.
5.6 Acid digestion of glass followed by either Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) or Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) can also be used for trace elemental analysis of glass, and offer similar detection levels and the ability for quantitative analysis. However, these methods are destructive, and require larger sample sizes and more sample preparation (Test Method E2330).
5.7 Micro X-Ray Fluorescence (µ-XRF) uses comparable sample sizes to those used for LA-ICP-MS with the advantage of being non-destructive of the sample. Some of the drawbacks of µ-XRF include lower sensitivity and precision, and longer analysis time (Test Method E2926).
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SCOPE
1.1 This test method covers a procedure for the quantitative elemental analysis of the following seventeen elements: lithium (Li), magnesium (Mg), aluminum (Al), potassium (K), calcium (Ca), iron (Fe), titanium (Ti), manganese (Mn), rubidium (Rb), strontium (Sr), zirconium (Zr), barium (Ba), lanthanum (La), cerium (Ce), neodymium (Nd), hafnium (Hf) and lead (Pb) through the use of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for the forensic comparison of glass fragments. The potential of these elements to provide the best discrimination among different sources of soda-lime glasses has been published elsewhere (1-5).2 Silicon (Si) is also monitored for use as a normalization standard. Additional elements may be added as needed, for example, tin (Sn) can be used to monitor the orientation of float glass fragments.
1.2 The method only consumes approximately 0.4 µg to 3 µg of glass per replicate and is suitable for the analysis of full thickness samples as well as irregularly shaped fragments as small as 0.1 mm by 0.1 mm by 0.2 mm (6) in dimension. The concentrations of the elements listed above range from the low parts per million (µgg-1) to percent (%) levels in soda-lime glass, the most common type encountered in forensic cases. This standard method can be applied for the quantitative analysis of other glass types; however, some modifications in the reference standard glasses and the element menu may be required.
1.3 This standard is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practice E2917), and demonstrated proficiency to perform forensic casework.
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
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SIGNIFICANCE AND USE
5.1 The overarching goals of the forensic analysis of geological materials include (A) identification of an unknown material (see 11.3), (B) analysis of soils, sediments, or rocks to restrict their possible geographic origins as part of a provenance analysis (see 11.4), and (C) comparison of two or more samples to assess if they could have originated from the same source or to exclude a common source based on observation of exclusionary differences (see 11.5). XRD is only one analytical method that can be applied to the evidentiary samples in service of these distinct goals. Guidance for the analysis of forensic geological materials can be found in Refs (2-4).
5.2 Within the analytical scheme of geological materials, XRD analysis is used to: identify the crystalline components within a sample; identify the crystalline components separated from a mixture, typically clay-sized material (see 8.8), or a selected particle class for which additional analysis is needed (see 8.11); or compare two or more samples based on the identified crystalline phases or diffraction patterns (see 11.5).
5.2.1 Non-destructive XRD analysis can be performed in situ on geological material adhering to a substrate (see 8.12.3).
5.2.2 The most common forensic applications of XRD to geological materials are (A) identification or confirmation of a selected phase or fraction of a sample (see 8.12), (B) identification of minerals in the clay-sized fractions of soils (see 8.8), and (C) identification of the phases of the hydrated cement component of concrete or mortar.
5.3 This guide is intended to be used with other methods of analysis (for example, polarized light microscopy, scanning electron microscopy, palynology) within a more comprehensive analytical scheme for the forensic analysis or comparison of geological materials.
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1.1 This guide covers techniques and procedures for the use of powder X-ray diffraction (XRD) in the forensic analysis of geological materials (to include soils, rocks, sediments, and materials derived from them such as concrete), to enable non-consumptive identification of solid crystalline materials present as single components or multi-component mixtures.
1.2 This guide makes recommendations for the preparation of geological materials for powder XRD analysis with adaptations for samples of limited quantity, instrumental configuration to generate high-quality XRD data, identification of crystalline materials by comparison to published diffraction data, and forensic comparison of XRD patterns from two or more samples of geological materials to support criminal investigations.
1.3 Units—The values stated in SI units are to be regarded as standard. Other units are avoided, in general, but there is a long-standing tradition of expressing X-ray wavelengths and lattice spacing in units of Ångströms (Å). One Ångström = 10–10 meter (m) = 0.1 nanometer (nm).
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4.1 The design and configuration of an audio laboratory, as well as the maintenance of equipment, are factors that must be considered to ensure an optimal environment to produce the best results. This guide is intended to provide general guidance for laboratory setup and maintenance.
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1.1 This guide sets forth recommendations for the creation of a forensic audio laboratory space as well as the configuration, verification, and maintenance of the equipment contained within the lab.
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SIGNIFICANCE AND USE
4.1 A training program provides the theoretical foundation and practical skills necessary for a trainee to become a qualified forensic hair examiner.
4.2 A trainee is directly supervised by a qualified examiner throughout their training. At the end of the training program, a successful trainee is capable of forming opinions, presenting and explaining evidence, and understanding the limitations of analytical results and interpretations based upon sound scientific knowledge, validated procedures, and practical experience.
4.3 A trainee is required to meet the minimum training criteria in Practice E2917 and this practice. It is the laboratory management’s responsibility to ensure the selected trainee has the appropriate educational background. It is recommended that, at a minimum, the trainee possess a bachelor’s degree in a natural science.
4.4 This document outlines lessons, practical exercises, and criteria to monitor and evaluate trainee progress and is designed to be incorporated into an overall laboratory training program.
4.5 Additional training beyond that which is listed here should be made available to the trainee. Such training might include off-site courses, internships, and specialized training by experienced examiners. Continuing education and training will provide a forensic examiner the opportunity to remain current in the field.
4.6 Additional analyses can be performed on hairs that have been chemically altered (for example, dyed hair) or have trace materials on the surface (for example, glitter). Such techniques are beyond the scope of this document.
4.7 This practice addresses the benefit of following microscopical examinations with DNA analysis.
SCOPE
1.1 This practice covers training guidelines for use by forensic laboratory personnel responsible for training forensic examiners that will perform hair examinations, including microscopical comparisons of human hair.
1.2 Forensic hair examiners are trained in accordance with Practice E2917 and the discipline-specific guidelines (Guide E3316) and criteria within this practice.
1.3 This practice contains guidelines that include the tasks, goals, and objectives that allow the trainee to acquire the requisite knowledge, skills, and abilities to independently perform casework in the microscopical examination of hair.
1.4 This practice addresses the correlation between the analytical results of microscopical examinations and the potential for DNA analysis.
1.5 This practice addresses training for the microscopical examination of hairs and not the examination of chemical alterations (for example, hair dye) or trace materials on the surface of hairs (for example, hair care products).
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SIGNIFICANCE AND USE
4.1 This guide describes good practices for the collection (5), packaging, and preservation (8.3) of soils in criminal forensic investigations. Some of the information in this guide is demonstrated in its companion video, which is available on-line and is intended as a complementary resource to this guide (6).
4.2 Individual agencies can use this guide to develop agency-specific procedures regarding the collection of soils for forensic applications.
SCOPE
1.1 This standard provides guidance to instruct crime scene professionals in good practices for the documentation, collection, and preservation of soil and other geological evidence for use in criminal investigations. Sampling for environmental geology is outside of its scope. It is designed as a resource for professionals whose job responsibilities include the collection and preservation of soil evidence and for forensic scientists to enable them to advise crime scene investigators.
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.
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SIGNIFICANCE AND USE
4.1 µ-XRF is a nondestructive qualitative elemental analysis technique used for polymers. It involves excitation of a sample by an X-ray source resulting in the emission of characteristic X-rays detected using an energy dispersive X-ray detector. Results are displayed simultaneously as a spectrum of intensity as a function of energy for elements of atomic number 11 or greater.
4.2 µ-XRF enables the determination of the elemental composition of a specimen and can be utilized for comparisons of components of polymeric materials (for example, tape backings, tape adhesives, paint layers).
4.3 Comparisons of X-ray spectra acquired from polymer samples are conducted for source discrimination or potential association.
4.4 Quantitative processes for µ-XRF analysis are available but are not used for polymer analyses because of the lack of prepared polymer standard reference samples.
4.5 In general, information available from a heterogeneous specimen diminishes as its size is reduced or its condition degrades, which lessens its likelihood of being representative of the source material.
4.6 µ-XRF data collected from polymers is limited to specific information (for example, elements detected, relative elemental abundance); additional analytical procedures are required to further characterize and identify the chemical composition of the polymer sample.
4.7 Limitations of µ-XRF include the inability to detect some elements in trace concentrations, the inability to analyze individual particles, the potential interference related to the penetration depth of the beam relative to the sample thickness, the inability to resolve the peaks of some elements (for example, Ba Lα / Ti Kα), and the potential for discoloration of some materials due to exposure to radiation.
SCOPE
1.1 This guide covers recommended techniques and procedures intended for use by forensic laboratory personnel that perform µ-XRF analysis of polymer samples.
1.2 This guide describes various techniques and procedures used in the µ-XRF analysis of polymers that include sample handling and preparation, instrument operating conditions, and spectral data collection, evaluation and interpretation.
1.3 This guide describes the application of µ-XRF systems equipped with either mono- or poly- capillary optics and an energy dispersive X-ray detector (EDS).
1.4 This guide is intended to be applied within the scope of a broader analytical scheme (for example, Guide E1610, Guide E3260) for the forensic analysis of a polymer sample (1-6).2 A µ-XRF analysis can provide additional information regarding the potential relationships between the sources of polymeric materials.
1.5 The fundamental aspects of the composition and manufacture of polymeric materials or theory of X-ray fluorescence can be found in various texts (7-18).
1.6 This standard is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practices E2917, E3233, E3234), and demonstrated proficiency to perform forensic casework.
1.7 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.8 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.9 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
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SIGNIFICANCE AND USE
5.1 TLC is an inexpensive and simple technique that could be used to complement other analytical techniques within a general analytical scheme related to forensic fiber examination.
5.2 Consider the forensic analysis of fiber colorants using TLC for single fiber comparisons only when the sample size is adequate (that is, enough colorant can be extracted for analysis) and it is not possible to discriminate between the fibers of interest using other techniques, such as comparison microscopy and MSP. Larger fibrous units (for example, thread or tuft) can be treated as an individual sample if determined to be homogeneous. Do not treat fibers that cannot be directly related to each other as a collective sample for the purposes of TLC.
5.3 The extraction procedures carried out prior to TLC analysis can provide useful information about dye classification. TLC can provide qualitative information about dye components. Similar colors made up of different dye components can be differentiated using this technique. The application of TLC may serve to discriminate between fibers or it may support the possibility of fibers sharing a common source.
5.4 TLC can be prohibitively difficult or undesirable in some circumstances. Short lengths of fibers or pale-colored fibers can lack adequate amounts of colorant necessary to be examined by TLC. Dye extraction from some fibers can be impossible (2, 3). Some fiber types do not truly extract, but change or lose color. Reactive dyes are covalently bonded to the fiber and typically cannot be removed by conventional extraction methods, but can be released from cotton and wool by disrupting the fiber by enzymatic or chemical digestion, respectively (1). The desire to preserve evidence from deleterious change or for possible analysis by another examiner can preclude removing the color or employing a destructive method for analysis.
SCOPE
1.1 This guide is intended as an overview of the Thin-Layer Chromatography (TLC) of fiber colorants (or individual dye components) present in dyed fibers. It is intended to be applied within the scope of a broader analytical scheme for the forensic analysis of fiber samples. TLC could provide information that cannot be obtained through other color analyses (such as microspectrophotometry (MSP)) (1).2
1.2 This standard is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practice E2917), and demonstrated proficiency to perform forensic casework (see Practice E3255).
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
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SIGNIFICANCE AND USE
4.1 Color is an easily observable characteristic of soils and is integral to the taxonomic classifications of soils (6-8); factors including parent material, hydrology, vegetation, and extent of soil weathering, can affect soil color, making color a valuable diagnostic tool for forensic examination purposes.
4.2 Soil color is sufficiently variable among soils to be used for differentiation of many soils in forensic examinations (9, 10) (see Section 6 for the test method for color determination and comparison criteria) as determined by visual characterization in the Munsell color system.
4.3 Instrumental techniques are suitable for color determination of soil evidence but are not covered within this practice.
4.4 Color determinations of soil samples are also used within soil provenance assessments to provide investigative leads or aid in searches. Interpretation of soil color for soil provenance is case-specific and beyond the scope of this practice, but the methods of color determination (6.5.1 to 6.5.2) and documentation (6.7) described here should be applied to soil color within soil provenance cases.
SCOPE
1.1 This practice covers visual color determination of soil/geologic material within the context of a forensic examination and is intended for use by laboratory personnel.
1.1.1 This practice recommends use of soil color for: the initial screening of soil samples in forensic casework, prioritization of known soil exemplars for detailed analysis, and includes a test method for color determination in the Munsell color system and comparison among samples.
1.2 Units—Units in the Munsell color system are used throughout this document.
1.3 This practice is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practice E2917), and demonstrated proficiency to perform forensic casework.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
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SIGNIFICANCE AND USE
5.1 This guide is designed to assist an examiner in the selection of appropriate sample preparation methods for the analysis, comparison, and identification of fibers using IR spectroscopy. IR spectroscopy can provide additional compositional information than is obtained using polarized light microscopy alone. The extent to which IR spectral comparison is conducted will vary with specific sample and case evaluations.
5.2 IR analysis should follow visible and fluorescence comparison microscopy, polarized light microscopy, and ultraviolet (UV)/visible spectroscopy. If no exclusionary differences are noted between the known and unknown samples in optical properties, then proceed to IR spectroscopy as the next step in the analytical scheme, as applicable.
Note 1: IR analysis generally follows the aforementioned techniques since sample preparation (for example, flattening) irreversibly changes fiber morphology.
5.3 IR spectroscopy should be conducted before dye extraction for chromatography due to the semi-destructive nature of the extraction technique. Because of the large number of sub-generic classes, forensic examination of acrylic and modacrylic fibers is likely to benefit significantly from IR spectral analysis (5). Useful distinctions between subtypes of nylon and polyester fibers can also be made by IR spectroscopy.
5.4 IR spectroscopy can provide molecular information regarding major organic and inorganic components. Components in lesser amounts are typically more difficult to identify. Reasons for this include interference of the absorption bands of the major components with the less-intense bands of minor components, and sensitivity issues whereby the minor components are present at concentrations below the detection limits of the instrument.
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SCOPE
1.1 Infrared (IR) spectroscopy is a valuable method of fiber polymer identification and comparison in forensic examinations. The use of IR microscopes, coupled with Fourier transform infrared (FTIR) spectrometers, has greatly simplified the IR analysis of single fibers, thus making the technique feasible for routine use in the forensic laboratory. This guide provides basic recommendations and information about IR spectrometers and accessories, with an emphasis on sampling techniques specific to fiber examinations. The particular method(s) employed by each examiner or laboratory will depend upon available equipment, examiner training, sample suitability, and sample size.
1.2 This guide is intended for examiners with a basic knowledge of the theory and practice of IR spectroscopy, as well as experience in the handling and forensic examination of fibers. In addition, this guide is to be used in conjunction with a broader analytical scheme.
1.3 If polymer identification is not readily apparent from optical data alone, an additional method of analysis, such as microchemical tests, melting point, IR spectroscopy, Raman spectroscopy, or pyrolysis gas chromatography, should be used. An advantage of IR spectroscopy is that the instrumentation is readily available in most forensic laboratories and the technique is minimally destructive.
1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.5 This standard is intended for use by competent forensic science practitioners with the requisite formal education, discipline-specific training (see Practice E2917), and demonstrated proficiency to perform forensic casework.
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practice...
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