OSAC 2022-S-0008 Standard Guide 

for Facial Image Comparison Documentation

1

OSAC 2022-S-0008

Standard Guide for Facial 

Image Comparison 

Documentation

Facial Identification Subcommittee

Digital/Multimedia Scientific Area Committee

Organization of Scientific Area Committees (OSAC) for Forensic Science
OSAC 2022-S-0008 Standard Guide 

for Facial Image Comparison Documentation

2

Draft OSAC Proposed Standard

OSAC 2022-S-0008 

Standard Guide for Facial 

Image Comparison 

Documentation

Prepared by 

Facial Identification Subcommittee

Version: 1.0 

March 2022

Disclaimer:

This OSAC Proposed Standard was written by the Facial Identification Subcommittee of the 

Organization of Scientific Area Committees (OSAC) for Forensic Science following a process 

that includes an open comment period. This Proposed Standard will be submitted to a standards 

developing organization and is subject to change. 

There may be references in an OSAC Proposed Standard to other publications under 

development by OSAC. The information in the Proposed Standard, and underlying concepts and 

methodologies, may be used by the forensic-science community before the completion of such 

companion publications.

Any identification of commercial equipment, instruments, or materials in the Proposed Standard 

is not a recommendation or endorsement by the U.S. Government and does not imply that the 

equipment, instruments, or materials are necessarily the best available for the purpose.
OSAC 2022-S-0008 Standard Guide 

for Facial Image Comparison Documentation

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1 Standard Guide for Facial Image Comparison Documentation

2 1. Scope

3

4 1.1 The purpose of this document is to provide minimum guidelines and a common 

5 baseline of information for facial image comparison documentation.

6

7 1.1.1 Documentation may be in the form of notes, images with markups and 

8 annotations, narratives, worksheets, electronic records, investigative lead or forensic 

9 reports, or any combination of these methods.

10

11 1.2 This document does not discuss methods for how to conduct a facial image 

12 comparison, opinion scale(s), or details that may be agency specific.

13

14 2. Referenced Documents

15

16 2.1 ASTM Standards:

17 E3149 Standard Guide for Facial Image Comparison Feature List for Morphological

18 Analysis

19

20 2.2 Other Standard Documents

21 FISWG Physical Stability of Facial Features of Adults

22 FISWG Guide for Role-Based Training in Facial Comparison

23 FISWG Standard Practice/Guide for Image Processing to Improve Automated Facial 

24 Recognition Search Performance

25 FISWG Facial Comparison Overview and Methodology Guidelines

26 OSAC Standard Framework for Developing Discipline Specific Methodology for 

27 ACE-V

28

29 3. Terminology

30

31 3.1 Definitions

32 3.1.1 Forensic Report: a document whose intent is to provide information to assist a 

33 trier of fact (e.g., judge or jury).

34 3.1.2 Investigative Lead Report: a document whose intent is to provide information 

35 to assist operational personnel (e.g., investigator, detective, or analyst).

36

37 4. Summary of Guide

38

39 4.1 This guide discusses the items that a practitioner should document when 

40 documenting facial image comparisons.

41

42 5. Significance and Use

43

44 5.1 These guidelines should be used as a reference by the practitioner to 

45 adequately document the facial image comparison.
OSAC 2022-S-0008 Standard Guide 

for Facial Image Comparison Documentation

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46 5.2 This document outlines the information needed to provide a clear 

47 understanding of the process conducted during a facial image comparison to the recipient.

48 5.3 The sections below provide the recommended minimum guidelines for 

49 information that should be documented in accordance with the type of report and 

50 agency specific needs.

51

52 6. Items to Document for a Facial Image Comparison

53 These items are not presented in order of importance or priority.

54

55 6.1 Administrative Data

56 6.1.1 Case Identifier

57 6.1.2 Dates

58 6.1.2.1 Date Received

59 6.1.2.2 Date Searched/Compared

60 6.1.2.3 Date of Image Capture (if available)

61 6.1.3 Requestor(s)

62 6.1.3.1 Contact Information

63 6.1.4 Any Written/Verbal Correspondence

64 6.1.5 Relevant Case Information (if provided)

65 6.1.6 Organization Conducting Examination

66 6.1.6.1 Contact Information

67 6.1.6.2 Practitioner(s)

68 6.1.7 Details and Scope of the Request (if provided)

69 6.1.8 Origin of Images

70 6.1.9 Filename/Identifier of Images Received.

71 6.1.10 Indication of whether a facial recognition (FR) search was conducted and 

72 results (if applicable).

73 6.1.10.1 Gallery Searched.

74 6.1.10.2 Number of Candidates Returned (based on maximum number returned or 

75 threshold used).

76 6.1.10.3 Ranking of returned potential candidate(s) if returned list is not randomized

77 6.1.11 Disclaimer – Agencies should include in all facial image comparison reports 

78 their own disclaimer identifying and general limitations of the recommended usage of the 

79 report. 

80 6.1.12 Reference to Comparison Method used.

81 6.1.13 Description of the disposition of all items received. 

82

83 6.2 Analysis

84 6.2.1 Determination of image applicability in the context of the question (e.g., 

85 Question asked is: “Are these two people the same?” However, the images of the two 

86 persons display a large age difference and were taken days apart, then the persons cannot be 

87 the same. 

88 6.2.2 Indication of images that do or do not meet agency specific requirements for 

89 comparison.

90 6.2.2.1 Explanation for determination that images do not meet specific requirements.
OSAC 2022-S-0008 Standard Guide 

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91 6.2.3 Image Analysis Documentation (e.g., lighting conditions, image resolution, 

92 etc.)

93 6.2.4 Processed image(s) (if applicable).

94 6.2.4.1 Filename/Identifier of processed image(s) (if applicable).

95 6.2.4.2 Steps taken to process images. 

96

97 6.3 Comparison

98 6.3.1 Documentation of the comparison

99 6.3.1.1 Compare and document features of the face visible in each image, as defined 

100 in the ASTM E3149 Facial Image Comparison Feature List for Morphological Analysis. 

101 6.3.1.2 A documented account of the compared features.

102 6.3.2 Observed effects of imaging conditions and physical stability of facial 

103 components or component characteristics. 

104 6.3.3 A visual example of the compared facial images. 

105

106 6.4 Evaluation

107 6.4.1 Opinion Scale used

108 6.4.1.1 Definitions or information and interpretation of what drives an opinion (if 

109 applicable)

110 6.4.2 Opinion reached

111

112 6.5 Verification

113 6.5.1 Verifier’s name, date, and result of verification.

114 6.5.2 If the examination is not verified by a second examiner, a disclaimer that the 

115 comparison is not verified must be included in the report. 

116

117 7. Additional Information

118

119 7.1 In accordance with the Agency’s data retention policies, the following should 

120 also be saved (hard/digital):

121 7.1.1 All correspondence (e.g., email, case notes, reports, etc.)

122 7.1.2 Received images

123 7.1.3 Processed images

124 7.1.4 Chain of Custody

125 7.1.5 Disposition (if applicable)

126

127 7.2 There should be documentation within the agency on the following:

128 7.2.1 Algorithm

129 7.2.1.1 Name of Algorithm Vendor

130 7.2.1.2 Version

131 7.2.1.3 Specific configurations

132 7.2.1.4 Date implemented

133 7.2.2 Software

134 7.2.2.1 Vendor name

135 7.2.2.2 Version
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136 7.2.2.3 Specific Configurations

137 7.2.2.4 Date implemented

138

139 7.3 Agency Accreditation

140 7.3.1 Reference to agency comparison method

141 7.3.2 Reference to agency Standard Operating Procedures (SOP)

142

143 7.4 Practitioner Qualifications

144 7.4.1 Training

145 7.4.2 Certification

146