When your career, clearance, military service, liberty, immigration status, or ability to work depends on a government decision, legal knowledge alone may not be enough.

You need a team that understands how the government investigates facts, evaluates credibility, measures risk, exercises discretion, and builds the record on which that decision will be made.

National Security Law Firm was built for those moments.

Our attorneys include former judges and government decision-makers, a presidentially appointed former United States Attorney, former federal and military prosecutors, former defense counsel, former agency attorneys, military leaders, senior government leaders, and national-security professionals.

They have served inside many of the institutions our clients must now confront.

Today, NSLF brings those perspectives together to represent individuals, service members, federal employees, contractors, families, and businesses in high-stakes federal and military matters throughout the United States and overseas.

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Former Judges · Former Prosecutors · Former Government Counsel · Military Leaders · Nationwide Representation

The Government Does Not Evaluate Your Case From One Perspective

A federal or military matter may pass through investigators, agency attorneys, prosecutors, commanders, adjudicators, administrative judges, or senior government officials. Each role may examine the same facts differently—and each may identify a different weakness.

An investigator may test whether your account is complete and consistent. An agency attorney may evaluate legal exposure and institutional risk. A prosecutor may search for admissions or contradictory evidence. An adjudicator or judge may determine whether the record is credible enough to support a favorable decision.

That is why NSLF was not built around a single type of lawyer.

We bring together professionals who have occupied different roles throughout federal, military, administrative, and national-security systems. That allows us to examine important matters from more than one professional perspective, anticipate how the government may respond, and coordinate the strategy when one problem affects multiple proceedings.

Learn Why NSLF Is Different

Why We Built National Security Law Firm

People confronting the federal government are often forced to navigate fragmented systems.

A service member under investigation may also face a security-clearance suspension. A federal employee may face an employment action and a suitability determination arising from the same allegation. A contractor may encounter clearance, credentialing, and criminal consequences from a single event. An immigration or military-family matter may involve several agencies with different rules and priorities.

Hiring separate lawyers for each proceeding can create another danger: inconsistent strategies, duplicated work, and statements that help in one process but cause damage in another.

NSLF was created to address that problem.

We built a national firm with focused federal and military practice teams that can work together when matters overlap. Each attorney maintains depth in a defined area, while the broader firm provides the institutional experience needed to recognize consequences beyond the document or deadline immediately in front of the client.

Our purpose is not simply to answer the government. It is to understand the complete system surrounding the client—and protect the client’s position within it.

Why Clients Choose National Security Law Firm

When the federal government controls the outcome, legal knowledge alone may not be enough. You need attorneys who understand how government officials investigate allegations, evaluate credibility, measure risk, exercise discretion, and build the record on which decisions are made.

NSLF brings together professionals who have made government decisions, represented federal agencies, prosecuted and defended cases, advised military and intelligence leaders, and challenged government action from the other side.

Former Government Decision-Makers

Our team includes a former Administrative Judge and Acting Chief Judge, a former U.S. Immigration Judge, and a former Acting Veterans Law Judge.

They have evaluated evidence, assessed credibility, applied federal standards, and issued decisions affecting clearances, immigration status, veterans’ benefits, careers, and futures. That experience helps our attorneys identify what a decision-maker will need to see before the government can justify a favorable outcome.

Former Federal and Military Prosecutors—and Defense Counsel

NSLF’s attorneys include a former United States Attorney, former Special Assistant U.S. Attorneys, former military and county prosecutors, and former military and civilian defense counsel.

They understand how allegations become investigations, how prosecutors identify weaknesses and inconsistencies, and how the government decides whether to proceed. Just as importantly, they understand how to challenge the government’s theory and protect the client when the facts are disputed.

Former Military Commanders and Senior Legal Advisors 

Our team includes current and retired colonels and lieutenant colonels, former Staff Judge Advocates, military commanders, Brigade Judge Advocates, and attorneys who advised Army Forces Command, U.S. Army South, Special Operations organizations, military intelligence units, and the 75th Ranger Regiment.

Military decisions are influenced by more than statutes and regulations. Command priorities, readiness, risk, credibility, and institutional concerns all matter. Our attorneys understand those pressures because they have advised the leaders responsible for making those decisions.

Former Intelligence & National Security Attorneys

NSLF attorneys have advised Army intelligence organizations, supported counterintelligence investigations, worked inside INSCOM, represented the United States before the Foreign Intelligence Surveillance Court, handled FISA matters, and advised on classified information, insider threats, intelligence oversight, and national-security risk.

That experience is particularly valuable when a matter involves a security clearance, classified information, sensitive duties, intelligence-community employment, or allegations that may be interpreted as a broader national-security concern.

Former Agency Counsel Who Understand How the Government Builds its Case

Our attorneys have represented or advised the Department of Justice, Department of Homeland Security, Department of Defense, Defense Health Agency, Department of Veterans Affairs, and other federal organizations.

They have advised agency leadership, defended personnel actions, litigated on behalf of the government, conducted investigations, and evaluated administrative records. That perspective helps us anticipate the government’s arguments, identify what may be happening internally, and build a record designed to withstand agency review.

A Coordinated Team For Problems That Cross Federal Systems

A government problem rarely stays in one lane. A military investigation may threaten a security clearance. A criminal allegation may affect federal employment, immigration status, firearm rights, or a government credential. A statement made in one proceeding may be reused in another.

NSLF brings together focused practices in security-clearance law, military defense, federal employment, immigration, veterans’ matters, government contracts, federal investigations, and credentialing. When issues overlap, our attorneys can coordinate the strategy instead of treating each government action in isolation.

The government may evaluate your case through multiple offices, officials, and decision-makers. Your legal team should be capable of examining it from multiple perspectives too.

The People Behind America’s Federal Law Firm

Brett O’Brien

Attorney & Co-Founder
Former DOHA Joint Duty Experience & Army INSCOM Intelligence Law Attorney

Katherine O’Brien

Attorney & Co-Founder
Six-Time Super Lawyers Rising Star

Carl Marrone

Former Special Assistant U.S. Attorney
Former Military Prosecutor & Defense Counsel

Alex Carr

TSA, CBP & Federal Credentialing Attorney
FOIA & Government Records Attorney

Luke Rose

Former Department of the Army National Security Attorney
Former Brigade Judge Advocate, 66th Military Intelligence Brigade

Duane “DAK” Kees

Former United States Attorney
Presidential Appointee · West Point Graduate

Sean Rogers

Former Army Special Victim Prosecutor
Army Lieutenant Colonel (Retired) · Former Defense Counsel

Katie Quintana

Former Administrative Judge
Former Acting Chief Judge, DOE Personnel Security & Appeals

Christopher Rittenhouse

Former Army Judge Advocate
Former Deputy Prosecuting Attorney & Special Victims’ Counsel

Alyssa Adams

Former Senior Department of Defense Attorney
Colonel & Commander, U.S. Army Reserve

Aaron Matthes

Former Defense Health Agency Labor & Employment Attorney
Former Army Prosecutor & Defense Counsel

Sara M. Tracy

Sara M. Tracy

Former USASOC Acquisition-Law Advisor
West Point Graduate · Army Lieutenant Colonel (Retired)

Dan Saumur

Former Staff Judge Advocate, U.S. Army South
Lieutenant Colonel, U.S. Army (Retired)

Justin Price

Justin M. Price

Former U.S. Immigration Judge
Former DHS Trial Attorney

Matthew R. Kalayjian

Former DOJ National Security Division Attorney-Advisor
Former Special Assistant U.S. Attorney & Navy Judge Advocate

Marcus J. Colicelli

Marcus J. Colicelli

Former Acting Veterans Law Judge
Senior Defense Counsel, U.S. Army Reserve

Of Counsel

John McGuire

Former Army FORSCOM National Security & Military Law Attorney
Former Acting Trial Counsel, 75th Ranger Regiment

Adam Davis

Merchant Mariner–Turned Maritime Attorney

National Security Law Firm’s Advisory Board

James C. “Jamey” Royse

Colonel, U.S. Army (Retired) · West Point Graduate
Former Assistant Chief of Staff for Intelligence, U.S. Army Central

Emilia DiSanto

Former Deputy Inspector General, U.S. Department of State
Former Senate Staff Director & Chief Investigative Counsel

Staff

Alicia McCray
Paralegal

Cara Sliger
Paralegal

Zena Hamdan
Paralegal

Sabrin Najjar
Paralegal

Janet Schnell
Paralegal

Victoria Rowles
Paralegal

Kayla Conners

Kayla Conners
Intake Specialist

Maria Gutierrez
Paralegal

Victoria Salinas
Paralegal

Alexis Nelson
Paralegal

Steven Ramirez-Bennett
Paralegal

Tamera Williams
Paralegal

Logan Nelson
Paralegal

Jennifer Roper
Paralegal

James Juaire
Paralegal

Mark Mosley Jr.
Paralegal

Veronica Stokes
Legal Intake Specialist