Matthew Lange Olmsted

Legal Advisor | Litigator | Prosecutor | Human Rights

Matthew Lange Olmsted's profile photo
LocationWashingtonDistrict of Columbia, United States
Government service11yrsU.S. Agency for International Development (USAID) · U.S. Department of State(DOS) · U.S. Department of Justice (DOJ)

About

I’m an attorney with more than 25 years of experience working at the intersection of international law, litigation, and public service. My career has taken me from courtrooms in the United States to post-conflict missions and diplomatic negotiations around the world. I’ve served as a Foreign Service Attorney with USAID, advising on complex legal and policy matters in Latin America, and previously as an Attorney-Adviser at the U.S. Department of State, focusing on human rights, refugee law, and investment disputes before international tribunals.

Earlier in my career, I prosecuted war crimes cases at the UN International Criminal Tribunal for the Former Yugoslavia, litigated federal cases as an Assistant U.S. Attorney, and worked on commercial disputes at a global law firm. I've also led legal reform and rule of law initiatives in Moldova, Micronesia, Georgia, and Kosovo. Across these diverse roles, I’ve remained committed to advancing justice, strengthening legal institutions, and promoting the rule of law.

Roles

Jul 2021–Sep 2025
Former role

Resident Legal Officer (Foreign Service) / FS-02

U.S. Agency for International Development (USAID), Office of the General Counsel

District of Columbia

Attorney AdvisorGrant Review Contract AttorneyForeign Relations / Diplomacy

Resident Legal Officer, Lima, Peru, September 2022 – September 2025

Provided comprehensive counsel to USAID Missions in Peru, Ecuador, and Paraguay on all aspects of foreign assistance operations for $300M+ in programming. Advised on program design, grants and contracts, fiscal and administrative law, employment and ethics, OFAC sanctions, and diplomatic privileges and immunities. Negotiated agreements with host governments and public international organizations, led risk management strategies, and ensured regulatory compliance. At the Agency’s headquarters, provided legal support to various Bureaus, Missions, and Offices by interpreting and advising on U.S. appropriations and fiscal laws, as well as applicable regulations and Agency policies.

Host Country and Stakeholder Engagement

·       Received Embassy Meritorious Honor Award for negotiating with the Peruvian Government key revisions to the $600M U.S.-Peru Development Objective Agreement.

·       Composed and successfully advocated for a project proposal to use $8M of U.S. Conflict Crisis Funds to address the escalating migration crisis in Peru, resulting in multiple contracts and grants to implementing partners.

·       Resolved legal barriers allowing Agency to contribute seed capital to a new conservation trust eventually to be funded through a Development Finance Corporation-financed debt conversion with Ecuadorian government.

·       Negotiated a $2M Project Contribution Agreement with UNICEF to regularize the legal status of migrant children in Peru – an initiative showcased during the USAID Administrator's visit to Peru.

Regulatory Compliance and Inter-Agency Coordination

·       Instigated changes to streamline and improve Agency’s congressional reporting policies, and then worked with Agency leadership to implement those changes Agency-wide.

·       Identified deficiencies in complying with U.S. anti-drug trafficking regulations, and coordinated responses throughout the region, including new operating procedures and training, preempting negative audit findings.

·       Formulated innovative contract provisions for agreements with implementing partners, ensuring compliance with environmental, small business, privacy, and data-protection requirements, and reducing audit risks.

·       Advised the Office of the Chief Financial Officer (CFO) and Missions on proper use of Agency appropriations under U.S. fiscal law, averting several potential Anti-Deficiency Act violations.

Ethics and Employment

·       Served as Ethics Officer for three Missions, providing daily counsel on conflicts of interest, financial disclosures, and whistleblower protections.

·       Collaborated with the Office of Inspector General, CFO, and Department of Justice to investigate and impose measures for fraud and funds control violations by Agency employees, as well as settlement of claims.

·       Worked with the USAID General Counsel’s Office and Agency Front Office to promote the first national staff member to Assistant Mission Director, advancing diversity within Agency leadership.

·       Advised Mission leadership and staff on evolving Executive directives aimed at realigning U.S. foreign assistance with the new Administration’s priorities, facilitating Mission compliance and a smooth wind down process.

Human Rights and International Law Expert

·       Counseled Missions on anti-NGO and other anti-democratic laws of host countries, mitigating security and financial risks to staff and implementing partners.

·       Advised technical teams on human rights standards (including freedom of expression and religion and privacy rights) in program activity implementation, ensuring compliance with U.S. and international law.

·       Worked closely with the Department of Justice and State Department to protect Mission inviolability under the Vienna Convention on Diplomatic Relations, preserving U.S. international rights vis-à-vis host governments.

Feb 2016–Jul 2021
Former role

Attorney-Adviser / GS-15

U.S. Department of State(DOS), Office of the Legal Adviser

District of Columbia

National SecurityCivil LitigationInternational Trade LawImmigration LawHuman Rights

Provided legal counsel on human rights, humanitarian, refugee, migration law and OFAC and visa sanctions. Advised on litigation strategy and compliance with U.S. and international legal obligations. Represented U.S. in bilateral agreement negotiations, investor-state and state-to-state arbitrations, and before UN bodies. Drafted legal memoranda, briefs, and policy guidance, Collaborated across U.S. agencies, foreign governments, and international organizations.

Human Rights Expert and International Negotiations

·       Advised on human rights law standards, including, refugee protections, arbitrary detention, elections, and economic, social and cultural rights, ensuring consistent application across bureaus.

·       Legal point of contact on all Organization for Security and Cooperation in Europe (OSCE) and European Court of Human Rights matters, ensuring alignment with U.S. and international human rights and humanitarian standards.

·       Represented the United States as a delegate to the UN General Assembly Third Committee, negotiating human rights resolutions and ensuring international consensus on key contemporary human rights issues.

·       Represented State Department in negotiations on memoranda of understanding with Central American countries related to asylum seekers, including several fact-finding missions to the region.

Inter-Agency Coordination

·       Advised inter-agency on the legal implications of the U.S. Asylum Cooperative Agreements and Title 42 restrictions, advocating for government-wide compliance with international non-refoulement obligations.

·       Coordinated with the Departments of Homeland Security, Justice, Health and Human Services, and other agencies to support U.S. human rights commitments, for which received a Meritorious Honor Award.

·       Determined factual sufficiency under human rights law of proposed Global Magnitsky and other sanctions, coordinating with Treasury and other agencies to ensure alignment with foreign policy and security objectives

·       Advised on drafting and implementing the first federal law providing diplomatic tools and authorities for diplomatic hostage release efforts, for which received a Meritorious Honor Award.

State-to-State Disputes

·       Represented the United States in multi-billion-dollar arbitrations before the Iran-U.S. Claims Tribunal (USCT), for which received multiple Superior Honor Awards and a Quality Performance Award.

·       Spearheaded identification, preparation, and examination of fact and expert witnesses, drafted briefs, presented evidence and oral arguments, and developed litigation strategies in IUSCT cases.

·       Supervised and trained junior attorneys on presentation of witness testimony before arbitration tribunals, ensuring effective examinations and providing unique opportunities for career development.

Investor-State Disputes

·       Advised on bilateral investment treaty arbitrations, authored non-disputing party submissions, and led U.S. positions in interagency coordination, reinforcing U.S. strategic posture on international investor-state law.

·       Represented the United States in a NAFTA dispute, eventually resulting in the dismissal of the case, for which received Meritorious Honor Award.

·       Supported U.S. citizens in international expropriation claims and managed sovereign immunity issues, exemplifying diplomacy at the legal frontier.

Jan 2008–Feb 2016
Former role

Trial Attorney (Prosecutor)

UN International Criminal Tribunal for the former Yugoslavia (ICTY)

The Hague, Netherlands

Criminal LawProsecutorCriminal InvestigationHuman Rights

Trial Attorney, Office of the Prosecutor

Prosecuted war crimes and crimes against humanity, leading complex investigations and managing interdisciplinary teams to collect and analyze evidence against senior political and military figures. Examined and cross-examined key witnesses, and drafted and argued legal briefs, motions, and appellate submissions, ensuring adherence to international legal standards and shaping ICTY jurisprudence through landmark cases.

·       Helped secure convictions addressing forced displacement, persecution, and attacks on civilians, strengthening the application of humanitarian law.

·       Planned and led complex investigations, managing diverse teams to analyze evidence against senior political and military figures, resulting in convictions that shaped jurisprudence and reinforced humanitarian protections.

·       Examined and cross-examined numerous victims, experts, and alleged perpetrators, and presented oral arguments. Mentored and supervised junior attorneys on witness presentations.

·       Spearheaded a pivotal evidence-gathering project central to cases, exposing the failure of civilian and military law enforcement to investigate or prosecute crimes against ethnic minorities – key to securing convictions.

·       Identified, prepared, and examined high-level police, prosecutorial, and judicial witnesses on failure of the criminal justice system to protect ethnic minorities, demonstrating systemic accountability gaps.

·       Authored and led drafting of legal briefs and appellate submissions, earning commendations for analytical rigor.

May 2007–Jan 2008
Former role

Criminal Law Legal Specialist

American Bar Association

Chisinau, Moldova

Attorney AdvisorConsulting

·       Designed and managed rule of law projects on anti-corruption and human trafficking.

·       Trained legal professionals and advised on legal reforms.

·       Led Moldova’s prosecution assessment (2008 PRI Report).

·       Co-authored a fair trial handbook based on ECHR jurisprudence.

·       Drafted grant and donor reports; coordinated with local and international stakeholders.

Oct 2004–May 2007
Former role

Assistant Attorney General

Department of Justice, Federated States of Micronesia

Palikir, Pohnpei, FSM

Attorney AdvisorInvestigationsLegislative AffairsProsecutor

·       Advised FSM President and Cabinet on legal and policy issues.

·       Drafted legislation on counter-terrorism, anti-money laundering, election law, and mutual assistance in law enforcement.

·       Litigated civil/criminal cases, including public corruption and constitutional matters.

·       Served as Acting Secretary of Justice in Secretary’s absence.

·       Established and trained Financial Intelligence Unit and represented FSM in regional legal and anti-money laundering conferences.

Apr 2002–Oct 2003
Former role

Assistant U.S. Attorney

U.S. Department of Justice (DOJ), Criminal Secrtion

California

Criminal LawProsecutorCriminal Investigation

·       Prosecuted federal crimes including smuggling, fraud, and re-entry offenses.

·       Presented cases to grand juries; conducted jury trials and argued motions.

·       Drafted briefs for District Court and Ninth Circuit Court of Appeals.

·       Supervised and guided work of law enforcement agents.

Oct 1997–Apr 2002
Former role

Associate Attorney

O'Melveny & Myers LLP

Washington, District of Columbia

Civil Litigation

·       Handled commercial litigation for corporate clients nationwide in state and federal courts.

·       Worked across practice areas: Regulatory, White Collar, Labor, Trademark, Trade.

·       Supervised junior attorneys and staff on litigation teams.