How to Evaluate a Digital Forensic Report—Part 1

Originally published on Legal Solutions Blog.

With the widespread permeation of advanced technology into our daily lives, it is inevitable that the products of those technologies, i.e., digital information, will make their way into the courtroom. This has largely occurred in the form of electronic discovery, or eDiscovery, where each party involved in the case provides the relevant information they possess. However, in cases where information may have been hidden, erased, or otherwise altered, digital forensic analysis is necessary to draw further conclusions. As in criminal cases, there are times when a gun in evidence is incontrovertibly the gun used in the crime, and times when it is necessary to trace the gun’s origin, run a fingerprint analysis, and compare bullet casings to ensure the weapon used and the weapon in evidence are one and the same.

Briefly, then, digital forensics is the preservation/retrieval and analysis of electronic data. This data includes the primary substantive data (the “smoking gun”) and the secondary data (the “fingerprints” on the data) such as data trails and time/date stamps. These and other metadata markers are often the key to establishing a timeline and correlating important events in a case.

A Brief History of Digital Forensics

In order for a forensic report to be scientifically valid, whether for digital or physical evidence, it must have conclusions that are reproducible by independent third parties. Facts discovered and opinions formed need to be documented and referenced to their sources. Such reports, containing opinions based upon well-documented digital sources of data, are much more likely to withstand judicial inquiry than are opinions based on less reliable or well-documented sources.  See for example Clark v. Takata Corp., where some expert opinions were excluded due to being based only on experience or training with no supporting scientific data or other rigorous methodology.

The reigning case in scientific evidence admission is Daubert v. Merrell Dow Pharmaceuticals Inc. This decision set forth a five-pronged standard for judges to determine whether scientific evidence is admissible in federal court.

In the next installment of this article, I’ll discuss the Daubert standard in detail.