EWJ August 62 2025 web - Journal - Page 74
Forensic Validation: Pay Attention
to the Man Behind the Curtain
by Jake Green, CCO, CCPA, CCPO, CASA, MCFE, Technical Operations Manager,
Digital Forensics – Envista Forensics
Forensic validation, a fundamental testing/
confirmation practice that is implemented across all
forensic disciplines, ensures the tools and methods
used to analyze evidence are accurate, reliable, and
legally admissible. Without it, the credibility of forensic findings—and the outcomes of investigations and
legal proceedings—can be severely undermined.
Whether in physical sciences like DNA analysis or
modern digital forensics, validation functions as a safeguard against error, bias, and misinterpretation.
volatile and easily manipulated nature of digital evidence. The rapid evolution of technology—including
new operating systems, encrypted applications, and
cloud storage—demands constant revalidation of
forensic tools and practices.
Digital forensic tools, like Cellebrite Inseyets and
Magnet AXIOM, and MSAB XRY, are frequently updated, and without proper validation, they may introduce errors or omit critical data. For instance, two
tools extracting data from the same mobile phone
may yield different results based on their parsing capabilities. Analysts must validate both the tools they
use and the steps they take to extract, preserve, and
interpret data.
Validation is vital for establishing scientific credibility
and gaining legal acceptance under standards, such
as the Frye and Daubert Standards. These frameworks require that scientific methods used in court be
generally accepted in the field or demonstrably reliable, often judged by factors such as testability, error
rates, and peer review.
Key validation practices in digital forensics include:
l Using hash values to confirm data integrity before
and after imaging
l Comparing tool outputs against known datasets
(test cases)
l Cross-validating results across multiple tools to
identify inconsistencies
What is Forensic Validation?
Forensic validation is the process of testing and
confirming that forensic techniques and tools yield accurate, reliable, and repeatable results. It encompasses
three key components:
l Ensuring logs and reports are transparent and
auditable
l Tool Validation ensures that the forensic software
or hardware performs as intended, extracting and
reporting data correctly without altering the source
Core Principles of Forensic Validation
l Reproducibility - Results must be repeatable by
other qualified professionals using the same method.
l Method Validation confirms that the procedures
followed by forensic analysts produce consistent outcomes across different cases, devices, and practitioners
l Transparency - All procedures, software versions,
logs, and chain-of-custody records must be thoroughly
documented.
l Error Rate Awareness - Forensic methods should
have known error rates that can be disclosed in
reports and during testimony.
l Peer Review - Validation processes should be
reviewed and ideally published to allow scrutiny from
the broader forensic community.
l Analysis Validation evaluates whether the interpreted data accurately reflects its true meaning and
context, ensuring that the software presents a valid
representation of the underlying evidence
Why does Forensic Validation Matter in Digital
Forensics?
Digital forensics presents unique challenges due to the
EXPERT WITNESS JOURNAL
72
AUGUST/SEPT 2025