Updated the Fingerprint Interest Group (FIG) page
with FIG #77; Potential Double Tap by I. Farrell of Texas. You can send your example
(anonymously if you desire) of unique distortion through
For discussion, visit the CLPEX.com forum FIG thread.
Updated the Detail Archives
We started off 2009
with a light Weekly Detail from the www.clpex.com
we review three recently posted SWGFAST updates
from the website, (www.swgfast.org). The text of the two represented
below is for convenience only, and the original document should always
be obtained and referenced from the SWGFAST website for official
Newly Approved and Posted Documents
Model Policy for Friction Ridge Examiner Professional Conduct
(12/23/08 ver 1.0)
Practitioners of the friction ridge examination discipline shall
regard themselves as members of a noble and honorable
profession. It is their duty to serve the interests of justice
to the best of their abilities at all times. They will be guided
by those practices and procedures which are generally recognized
within the profession to be consistent with a high level of
professionalism. Their motives, methods, and actions shall at
all times be above reproach and consistent with proper ethical
conduct. Professional conduct contrary to the principles
outlined in this model policy should be referred to an
appropriate enforcement authority.
1 Practitioners shall cooperate with other forensic science
professionals in order to promote the advancement of the
friction ridge examination discipline through scientific
research. Knowledge of any new discoveries, developments or
techniques applicable to the friction ridge examination
discipline shall be shared with the peer community.
2 Practitioners shall not undertake examinations or offer
testimony if unqualified to do so.
3 Qualifications of expertise are based on knowledge, skill,
education, experience and training, and shall not be
misrepresented by the practitioner.
4 Examinations shall be conducted utilizing accepted scientific
techniques and methods which are reliable, accurate and used
with appropriate standards and controls.
5 Techniques and opinions shall be based on facts and
interpretations and shall not be knowingly misrepresented.
6 Testimony shall be rendered in an impartial manner to promote
the understanding of examinations and findings.
7 Privileged communications shall be kept confidential.
Standard for Friction Ridge Digital Imaging
(12/23/08 ver 1.0)
These standards shall be applied to the digital recording and
depiction of friction ridge impressions that are to be used for
examination purposes. These standards do not extend to image
adjustments on an AFIS system. Policies and procedures must be
in place for the digital capture, storage, retrieval, display,
and transmission of friction ridge images retained as evidence.
This standard establishes requirements for the preservation of
identity, authenticity, integrity, and security of friction
ridge digital images. Prior to conducting digital imaging tasks
in friction ridge examination cases, examiners shall have
training appropriate to each task before them.
Agencies shall establish policies to determine which friction
ridge digital images will be retained as evidence.
2 Image Documentation
Friction ridge digital images, documentation, or associated data
shall include the following:
2.1 A unique case identifier. This association may be
accomplished by one or more of the following methods:
2.1.1 As part of the digital image.
2.1.2 As part of the file name.
2.1.3 As data associated with a digital image within an imaging
2.1.4 As data associated within a standardized record (i.e.,
ANSI NIST, Record Level 2).
2.2 Date and initials or personal marking.
2.3 Description or identifier of the item bearing the friction
2.4 Information about the orientation or position of the
friction ridge impression on the object through description,
diagram(s), or photograph(s).
2.5 Scene location or address, if other than the laboratory.
2.6 Accurate scale information.
2.7 Make and model of the capture device.
3 Image Quality
3.1 Friction ridge impressions to be used for comparison
purposes shall be captured (color or grayscale) at a minimum of
1000 ppi optical resolution when the image is sized 1:1.
Justification for any deviation from this standard shall be
documented on a case-by-case basis.
3.2 Grayscale digital imaging shall be at a minimum of 8 bits.
Color digital imaging shall be at a minimum of 24 bits.
3.3 Friction ridge impression digital images to be used for
comparison purposes shall be stored and transmitted without
compression or with lossless compression. Capture in a raw file
format is recommended.
4 Image Integrity
4.1 A primary image is the result of the first recording of an
image onto media. An original image is an accurate replica
(bit-for-bit value) of the primary image. Each original image
shall be stored in a manner which permits authentication.
4.2 Enhancement shall only be conducted on working copies of the
original image. Working copies used in forensic case examination
shall be saved as a separate copy and shall not replace the
4.3 Digital images captured from lifts or from conventional
photographs or negatives shall not replace the lift, negative,
or photograph as original images.
4.4 Agencies shall have procedures to ensure the accessibility
of digital images (e.g. images may be archived in a format to
ensure their accessibility, hardware and software may be
archived to ensure accessibility of images ).
5 Casework Documentation
5.1 Procedures shall be in place to ensure the accuracy and
completeness of documentation.
5.2 Casework documentation shall distinguish friction ridge
impression digital images from lifts or photographs.
5.3 The application of digital image processing (enhancement)
techniques shall be documented. This documentation shall be
sufficient to enable evaluation or replication of the digital
image processing techniques.
1. SWGIT, Best Practices for Archiving Digital and Multimedia
Evidence (DME) in the Criminal Justice System, 6/4/07, ver. 1.0,
Standard for Simultaneous Impression Examination
(12/5/08 ver 1.0)
text and images preclude posting here - please reference this
document from the SWGFAST website:
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