Sean Francis Mangan

Sean Francis Mangan

also known as LTC(Ret) Mangan, US Army, Mangan Law

5.0
Rating: 8.7

Licensed for 22 years

Military law Lawyer at Silverdale, WA
Practice Areas: Military Law, Criminal Defense, Family

10661 Old Frontier Rd NW, Suite 211, Silverdale, WA

About Sean

Biography

Practice Areas

3

Practice Areas

Military Law 90%

Military Criminal and Administrative Matters: Representation during investigations, Defense against Courts-Martial & Administrative Separations, Rebuttal to Letters of Reprimand, Negative Evaluations, and Medical Credentialing.

90%
Criminal Defense 8%

I primarily take cases for military family members arising from on-post incidents.

8%
Family 2%

I occasionally take on divorce and family law issues for military families.

2%

Fees and Rates

Cost

Free Consultation

$0 first 30 minutes


Payment Methods

  • Check
  • Credit Card

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Licenses

Licensed in Washington for 6 years

State: Washington

Acquired: 2019

Active

No misconduct found

Licensed in Oregon for 22 years

State: Oregon

Acquired: 2003

Inactive

No misconduct found

Location

Mangan Law

10661 Old Frontier Rd NW, Suite 211, Silverdale, WA, 98383

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Sean Francis Mangan's Reviews

Avvo Review Score

5.0 /5.0

122 Client Reviews

Showing 1 - 5 of 35 reviews | General Knowledge

Posted by KeAndrea Sanders | March 16, 2026

DUI Consultant

I want to personally thank Sean for not only the knowledge he just gave me, but also understanding my situation. Making sure I understand what’s next and what I need to do. Giving me pointers and understanding of what could happen. Thank you and I appreciate everything.

Posted by anonymous | September 29, 2025 | Military Law

Amazing Legal Advice

Sean gave great advice regarding a security clearance situation. He took time to fully understand my situation, courses of actions and likelihood, and confidence for me to make a better decision

Posted by anonymous | August 13, 2025 | Hired Attorney | Military Law

Expert Case Review & Options You Can Trust

As a senior NCO facing the QMP process, I hired him to review my case and provide clarity on my options. He was extremely thorough, professional, and responsive, taking the time to explain each step and give me the best options for my specific situation. His expertise and guidance gave me confidence ...moving forward, and I highly recommend him to anyone in a similar position

Posted by anonymous | March 21, 2025 | Hired Attorney | Criminal Defense

Exceptional Legal Representation – Highly Recommend

I am a Sergeant First Class on active duty in the U.S. Army, and I had the privilege of working with LTC Sean Mangan (Retired) during a difficult time when I was falsely accused of a crime and facing serious allegations. From the very first consultation, he demonstrated his extensive experience and l...aid out a clear, strategic plan to resolve my case. His professionalism, confidence, and deep understanding of the legal process immediately put me at ease. True to his word, Mr. Mangan executed his plan precisely, and within just a month of my initial contact with CID, he had my case completely closed out. His proactive approach, attention to detail, and commitment to justice were truly remarkable. I cannot recommend Mr. Mangan highly enough. If you need a knowledgeable, dedicated, and results-driven attorney, he is the one to have in your corner.

Posted by anonymous | December 04, 2024 | Hired Attorney | Military Law

I highly recommend LTC(Ret) Mangan. He is a highly experienced lawyer you can trust to defend you

I’m an Army NCO.  I was under investigation for actions I took both as a supervisor and activities in the course of my duties.  Even though I had done nothing wrong, my career was on the line and I didn’t trust the system to take care of me.  I knew needed legal representation from someone who unders...tood both Army administrative actions (NCOER's, 15-6’s) and duty specific action review. I found and hired LTC(Ret) Mangan because of his unique combination of military, legal, and law enforcement experience.  He worked with me to make sure the facts were straight and my interests were protected, He stayed in touch, even after-hours and on weekends.  With his help, I got my NCOER corrected to remove adverse comments and rating and received no adverse action from the investigation.  I highly recommend that you intrust LTC(Ret) Mangan to defend you.

See All Client Reviews

Sean Francis Mangan's Lawyer Endorsements

Endorse Sean
Paul Charles Judge headshot
Paul Judge

Military law lawyer | Nov 17

Relationship: Worked for lawyer

"I met Sean when I was a legal intern back in 2014. Now, we work together at The Law Offices of Sean F. Mangan, PLLC. I cannot say enough good things about Sean. He knows military law as good or better than anyone I have ever met. He is incredibly skilled in the courtroom. He is a thoughtful and creative problem solver with administrative issues. He has a deft hand with managing clients' problems and a wide network of professional relationships. I strongly recommend him and am proud to call him my mentor."

Amir Ragab Hamdoun headshot
Amir Hamdoun

Criminal defense lawyer | Aug 16

Relationship: Worked together on matter

"Sean Mangan is an expert litigator and a master in the courtroom. I had the fortune of working with Mr. Mangan on a criminal case that went to trial. The client's interests were represented to the full maximum potential. As an attorney, I would turn to Sean Mangan for tips on a wide spectrum of topics. I learned a great deal from Sean. With his knowledge base and calm demeanor, he made the trial team feel confident every step of the way. Sometimes, the battle is won before trial begins and Sean prepares his clients like no other. Highly recommend."

Cory Alan Chipman headshot
Cory Chipman

Military law lawyer | Jun 30

Relationship: Fellow lawyer in community

"I worked with Sean on several cases as his co-counsel. He is a knowledgeable professional with years of experience, including time as a military judge. He provided excellent representation to his clients and got results beyond expectations. Judges he practices in front of see him as a peer and respect his experience and arguments."

Jocelyn C. Stewart headshot
Jocelyn Stewart

Military law lawyer | Oct 16

Relationship: Worked together on matter

"Sean Mangan is one of the most knowledgeable and hardworking attorneys in his field. Dedicated and committed to every client and every case, Sean brings experience as a prior military judge, prosecutor, and defense attorney. I do not hesitate to endorse him."

Cody Elijah Harnish headshot
Cody Harnish

Military law lawyer | Sep 28

Relationship: Co-worker

"I wholeheartedly endorse this lawyer. Sean is an exceptional attorney with a ton of experience. What people cannot learn from experience, Sean naturally possesses. This means he is a knowledgeable, talented, and gifted lawyer."

View All Endorsements
Paul Charles Judge headshot
Paul Judge

Military law lawyer

Cody Elijah Harnish headshot
Cody Harnish

Military law lawyer

Experience

Rating:  8.7 (Excellent)

Honors

2010

Bronze Star Medal, DOD

2001

Superior Advocate Award- Mock Trial, University of Oregon School of Law

Work Experience

2020 - Present

Owner/Attorney, Mangan Law

2018 - 2020

Criminal Law Policy Attorney, US Army

2015 - 2018

Trial Judge, US Army

2013 - 2015

Regional Defense Counsel, Us Army Jag Corps

2010 - 2013

Professor of Criminal Law, TJAGLCS

2009 - 2010

Special Operations Legal Counsel, DOD/Joint Task Force

2008 - 2009

LLM Candidate, Us Army Jag Corps

2007 - 2008

Supervising Appellate Counsel, Us Army Jag Corps

2006 - 2007

Appellate Counsel, Us Army Jag Corps

2005 - 2006

Chief of Military Justice, Us Army Jag Corps

2005 - 2006

Special Assistant United States Attorney, Department Of Justice

2004 - 2004

Military Magistrate, Us Army Jag Corps

2003 - 2004

Administrative Law Attorney, Us Army Jag Corps

2002 - 2002

Intern Prosecutor, Lane County Prosecuting Attorney

2001 - 2002

Intern Prosecutor, Us Army Jag Corps

1996 - 2000

Officer, US Army Military Police

Associations

2021 - Present

Washington Defenders Association

Member

2020 - Present

International Association of Military Criminal Defense Lawyers

Member

2019 - Present

Washington State Bar Association

Member

2003 - Present

Oregon State Bar #035465

Member

2000 - Present

American Bar Association

Member

Sample of Legal Cases

United States v. Lt Col WH, USAF

NG to 10 of 11 charges. Appeal ongoing with USAF Ct of Criminal Appeals

United States v. SGT CB, US Army

Full Acquittal: Not Guilty to all Charges and Specifications

United States v. SGT RR, US Army

Not Guilty to all contested charges, no punishment adjudged

United States v. SFC CZ, U.S. Army

Full Acquittal, NG to All Charges and Specifications

See More Legal Cases

Education

2011

US Army Command & General Staff College

Leadership

2009

US Army JAG School

LLM Military Criminal Law

2003

University of Oregon School of Law

JD - Juris Doctor

1996

Gonzaga University

BA - Bachelor of Arts Sociology and Philosophy

Speaking Engagements

2016

Military Law Section (LAMP)

Military Justice Overview and Update

Publications

2020

US Army Army Regulation 27-10 (2019 edition)

2011

TJAGLCS-ADC Crimes and Defenses Deskbook

Languages

English

Activity

Avvo Rating

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