Principal
Justin M. Sedell
Practice Area
Family Law Notice
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Attorney bio
Justin’s practice concentrates on divorce, complex child custody disputes, collaborative law, and high conflict litigation. Justin is an experienced trial lawyer who represents clients facing a wide range of complicated family law disputes requiring sophisticated legal advice. He has practiced in Superior Courts throughout Western Washington and represents clients in the Washington State Court of Appeals and Supreme Court of Washington.
Education
Seattle University School of Law
Juris Doctor, cum laude, 2005
University of California at Davis
Bachelor of Arts, Political Science, 2002
Recognition & Activities
- Washington State Bar Association
- Adjunct Law Professor, Seattle University School of Law, 2007 – present
- Named Best Lawyers® 2023 “Lawyer of the Year” in Seattle in “Family Law”
- Recognized by The Best Lawyers in America® in the practice area of Family Law and Collaborative Law: Family Law
- Recognized as part of the LawDragon 500 Leading U.S. Family Lawyers, 2025
- Washington Law & Politics magazine “Super Lawyer”
- Named a ‘Rising Star’ by Washington Law & Politics and Washington Super Lawyers magazines, Family Law
- Member and prior Co-Chair, Judicial Evaluation Committee, QLaw Bar Association of Washington
- Member of King County Superior Court Unified Family Court Committee
- Prior Member, Alternative Dispute Resolution Committee, Washington State Bar Association
- Member, QLaw Bar Association
- Member, Washington State Bar Association, Family Law Section
- Member, International Association of Collaborative Professionals
- Member, Collaborative Professionals of Washington
- Member, King County Collaborative Law
Supplemental Education
- IACP Collaborative Law Training (International Association of Collaborative Professionals)
- IACP Facilitative Mediation Training (International Association of Collaborative Professionals)
Judicial Clerkships
- Law Clerk, Judge Mary I. Yu, King County Superior Court, 2005-2006
- Law Clerk, Judge Steven Gonzalez, King County Superior Court, 2006
- Washington State Bar Association
- Adjunct Law Professor, Seattle University School of Law, 2007 – present
- Named Best Lawyers® 2023 “Lawyer of the Year” in Seattle in “Family Law”
- Recognized by The Best Lawyers in America® in the practice area of Family Law and Collaborative Law: Family Law
- Recognized as part of the LawDragon 500 Leading U.S. Family Lawyers, 2025
- Washington Law & Politics magazine “Super Lawyer”
- Named a ‘Rising Star’ by Washington Law & Politics and Washington Super Lawyers magazines, Family Law
- Member and prior Co-Chair, Judicial Evaluation Committee, QLaw Bar Association of Washington
- Member of King County Superior Court Unified Family Court Committee
- Prior Member, Alternative Dispute Resolution Committee, Washington State Bar Association
- Member, QLaw Bar Association
- Member, Washington State Bar Association, Family Law Section
- Member, International Association of Collaborative Professionals
- Member, Collaborative Professionals of Washington
- Member, King County Collaborative Law
Supplemental Education
- IACP Collaborative Law Training (International Association of Collaborative Professionals)
- IACP Facilitative Mediation Training (International Association of Collaborative Professionals)
Judicial Clerkships
- Law Clerk, Judge Mary I. Yu, King County Superior Court, 2005-2006
- Law Clerk, Judge Steven Gonzalez, King County Superior Court, 2006
Publications & Presentations
Publications
- “Domestic Partnerships: Another Look, Additional Rights,” King County Bar Bulletin (2009)
- “A Family Law Practitioner’s Guide to Navigating the Domestic Partnership Expansion Bill,” Washington State Bar News, co-authored with Elizabeth Hershman-Greven (2008)
- “Washington’s Expanded Domestic Partnership Registry Grants Important New Rights for GLBT Couples,” Perspective, co-authored with Elizabeth Hershman-Greven (2008)
- “Legislature Acts Post-Anderson Domestic Partnership Bill Paves Way,” King County Bar Association Bar Journal, co-authored with Elizabeth Hershman-Greven (May 2007)
Presentations
- Speaker, AAML WA State Chapter Springt CLE – Cutting Edge Parenting Issues: Parental Relocation Disputes, Seattle, May 2024
- Speaker, “Family Law 101: What You Need to Know,” Pincus Professional Education (2015)
- Co-Chair, “WSBA Community Property Seminar,” Washington State Bar Association CLE (2012)
- Speaker, “Introduction to Collaborative Practice,” CLE for family law attorneys (2011)
- Speaker, “Parenting Plan Litigation,” King County Bar Association CLE (2010)
- Speaker, “Impacts of Washington’s Domestic Partnership Laws on the Elder Care Community,” CLE (2008, 2009)
- Speaker, “Parenting Plans and the Uniform Child Custody Jurisdiction and Enforcement Act,” King County Bar Association CLE (2009)
- Speaker, “Litigating Cases Involving Unmarried Couples,” Snohomish County Bar Association CLE (2009)
- Speaker, “Understanding Washington’s Domestic Partnership Legislation,” Tacoma Pierce County Bar Association CLE (2008)
- Speaker, “Relationship Agreements,” King County Bar Association CLE (2008)
- Speaker, “Washington State’s Domestic Partner Law,” Washington ACLU Seminar (2007)
- Speaker, Domestic Partner Law Forum, Equal Rights Washington Public Event, Tacoma, WA (2007)
Publications
- “Domestic Partnerships: Another Look, Additional Rights,” King County Bar Bulletin (2009)
- “A Family Law Practitioner’s Guide to Navigating the Domestic Partnership Expansion Bill,” Washington State Bar News, co-authored with Elizabeth Hershman-Greven (2008)
- “Washington’s Expanded Domestic Partnership Registry Grants Important New Rights for GLBT Couples,” Perspective, co-authored with Elizabeth Hershman-Greven (2008)
- “Legislature Acts Post-Anderson Domestic Partnership Bill Paves Way,” King County Bar Association Bar Journal, co-authored with Elizabeth Hershman-Greven (May 2007)
Presentations
- Speaker, AAML WA State Chapter Springt CLE – Cutting Edge Parenting Issues: Parental Relocation Disputes, Seattle, May 2024
- Speaker, “Family Law 101: What You Need to Know,” Pincus Professional Education (2015)
- Co-Chair, “WSBA Community Property Seminar,” Washington State Bar Association CLE (2012)
- Speaker, “Introduction to Collaborative Practice,” CLE for family law attorneys (2011)
- Speaker, “Parenting Plan Litigation,” King County Bar Association CLE (2010)
- Speaker, “Impacts of Washington’s Domestic Partnership Laws on the Elder Care Community,” CLE (2008, 2009)
- Speaker, “Parenting Plans and the Uniform Child Custody Jurisdiction and Enforcement Act,” King County Bar Association CLE (2009)
- Speaker, “Litigating Cases Involving Unmarried Couples,” Snohomish County Bar Association CLE (2009)
- Speaker, “Understanding Washington’s Domestic Partnership Legislation,” Tacoma Pierce County Bar Association CLE (2008)
- Speaker, “Relationship Agreements,” King County Bar Association CLE (2008)
- Speaker, “Washington State’s Domestic Partner Law,” Washington ACLU Seminar (2007)
- Speaker, Domestic Partner Law Forum, Equal Rights Washington Public Event, Tacoma, WA (2007)