Military Defense Investigation Knowledge Base
Military Defense Investigation Authority Publication
Authority Publication No. DI-146
Writing an Investigative Memorandum That Helps Counsel Act Without Turning Leads into Conclusions
Independent Military Defense Investigations
Supporting Attorneys, Service Members, and Families
Publication Date: August 24, 2026
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Executive Summary
Writing a military investigative memorandum requires the defense investigator to separate leads from verified facts, identify original sources and limitations, keep conflicts visible, and define unresolved issues without turning them into conclusions.
An investigative memorandum can influence how defense counsel understands a witness, record, timeline, or technical issue. If the memorandum blends observation, repetition, inference, and conclusion, unsupported assumptions can become embedded in the case.
DI-146 explains how investigators can write source-attributed memoranda that distinguish leads, verified facts, inferences, and conclusions while documenting chronology, corroboration, preservation, limitations, conflicts, and unsuccessful efforts.
The publication's practical example contrasts the unsupported statement that a witness 'lied' with a more useful memorandum that quotes the conflicting statements, identifies corroborating records, explains limitations, and leaves the credibility decision to counsel.
The purpose is to create a work product that lets counsel trace every important conclusion to its original source and move from every unresolved issue to a defined next step.
DI-146 explains how military defense investigators can write memoranda that report verified facts, sources, conflicts, limitations, unsuccessful efforts, and next steps without converting leads, inferences, or disputed information into unsupported conclusions.
Who Should Read This Publication?
Military Defense Counsel
Use source-attributed investigative memoranda to evaluate the evidence, identify conflicts and limitations, determine credibility and legal significance, and direct formal process or expert follow-up.
Defense Investigators
Use the reporting framework to distinguish leads, verified facts, inferences, and conclusions; document methods and sources; preserve conflicts; and identify unresolved issues without overstating what the evidence proves.
Service Members
Understand why careful investigative reporting matters and why an investigator's characterization should not replace the underlying witness statement, record, or other original evidence.
Experts and Consultants
Understand the importance of receiving complete underlying materials, clearly defined questions, and a record that distinguishes source evidence from summaries or investigator conclusions.
Families
Understand why a concise statement such as 'the witness lied' may be less useful to the defense than a documented comparison of conflicting statements, corroborating records, and known limitations.
Companion Video
This companion video expands on the investigative concepts presented in this Authority Publication through additional explanation, practical examples, and professional investigative insight.
About Michael West
The investigative guidance presented throughout these Authority Publications is based upon decades of professional experience conducting military, federal, criminal, civil, and private investigations. The principles discussed in these publications are drawn from real investigative work involving complex cases, witness development, evidence analysis, and factual case preparation.
Michael West has served as a Special Agent with the United States Air Force Office of Special Investigations (AFOSI) and the Department of Defense Inspector General, conducted federal background investigations, and spent decades working as a licensed private investigator supporting attorneys, businesses, service members, and private clients. Throughout his career, his work has focused on identifying facts, locating witnesses, analyzing evidence, and strengthening the factual foundation of legal cases through independent investigation.
The Military Defense Investigation Knowledge Base was created to share that investigative experience in a practical, understandable format. Its purpose is to help attorneys, service members, and families better understand the investigative process, ask more informed questions, and recognize opportunities where independent investigation may strengthen the defense.
Important Information
This Authority Publication is provided for educational and informational purposes and is intended to help readers better understand military defense investigations and the investigative process. It is based upon professional investigative experience and is designed to provide practical investigative insight rather than legal advice.
Every military case is unique. The investigative strategies, factual issues, and legal considerations applicable to one case may not apply to another. Readers should consult with a qualified attorney regarding legal rights, legal strategy, and decisions involving their individual circumstances.
Nothing contained in this publication should be interpreted as creating an attorney-client relationship or an investigator-client relationship. References to investigative techniques, procedures, or case examples are provided solely to illustrate investigative principles and should not be considered legal guidance.
Effective military defense is strengthened by informed legal representation supported by thorough factual investigation. The purpose of these Authority Publications is to help readers better understand that investigative process so they can communicate more effectively with qualified legal counsel and make informed decisions throughout the military justice process.