Chain Of Custody Explained

Who Should Read This Publication?

This publication is particularly valuable for:

Military defense counsel — When physical, biological, digital, or other evidence plays an important role in an allegation, counsel should understand how that evidence was collected, handled, stored, transferred, examined, and preserved. A complete chain-of-custody review may identify questions affecting the reliability or interpretation of the evidence.

Civilian attorneys representing service members — Attorneys should not assume that an evidence label or laboratory report establishes an uninterrupted history. Reviewing the underlying collection records, property documentation, transfers, evidence seals, storage information, and testing records can reveal issues requiring further investigation.

Defense investigators — Investigators may need to reconstruct the complete history of an important item of evidence. This includes determining who collected it, how it was identified and packaged, where it was stored, who had access to it, when it was transferred, what examinations were performed, and whether its condition changed.

Attorneys and investigators handling forensic or laboratory evidence — DNA, toxicology, drug testing, firearms evidence, electronic devices, and other forensic materials may pass through numerous individuals and facilities before the results appear in a report. Understanding that history helps determine whether the evidence tested is reliably connected to the evidence originally collected.

Legal teams confronting missing or unexplained documentation — A gap in the chain of custody does not automatically mean that evidence was altered or tampered with. It does, however, create a factual question that may require additional records, interviews, photographs, laboratory documentation, or testimony to resolve.

Investigators examining possible contamination, alteration, or improper storage — The manner in which evidence is packaged, sealed, transported, stored, accessed, and tested can affect its condition and evidentiary value. Investigators should determine whether established procedures were followed and, more importantly, whether any deviation could have affected the evidence.

Attorneys seeking independent examination or testing — Chain-of-custody issues become particularly important when the defense needs access to evidence for independent testing. Investigators should determine whether the original evidence still exists, its present condition and location, and what testing or handling has already occurred.

Service members and families seeking to understand how evidence is handled — This publication explains why investigators do not simply accept an item of evidence at face value. Establishing where it came from, what happened to it, and whether it can reliably be connected to the case is part of determining what that evidence actually establishes.