León Castellanos-Jankiewicz

International law expert on arms trade and human rights

Recent publications

European Defence & Security Law & Policy Quarterly (2026)

ReArm Europe and the Rule of Law

The Right to a Remedy for Wrongful European Arms Exports

George Washington Int’l Law Review (2025)

Symposium: New Pathways Toward Supply Chain Accountability

American Journal of Int’l Law Unbound (2024)

My work appears in

The logo of NRC, a national publication in The Netherlands.
Al Jazeera logo with gold calligraphy and text
The logo of El País, a global newspaper based in Spain.
BBC World Service logo with a red background, featuring three white squares with red letters 'B', 'B', and 'C', and the words 'WORLD SERVICE' in white below.
Nexos logo in black text.
Logo of Reforma, a Mexican organization, featuring a yellow winged figure with a sword inside a green circle.
Logo of Just Security with a stylized Capitol building dome replacing the letter 'I' in 'JUST', with the tagline 'A Forum on Law, Rights, and U.S. National Security' underneath.

Interviews & press

  • 'The responsibility of gunmakers doesn’t end at the factory gate'

    El País, June 11, 2025

    Read

  • Google worried it couldn’t control how Israel uses project Nimbus, files reveal

    The Intercept, May 13, 2025

    Read

  • Can Mexico win its battle with US gun companies?

    BBC, March 7, 2024

    Listen

New report

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New report *

Close-up of a single bullet cartridge standing upright with other cartridges and a firearm blurred in the background.

Access to Justice for Wrongful Arms Transfers

A project under my supervision at the University of Amsterdam Law Clinics

International Law Clinic

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Selected speeches & talks

  • Two men in suits sitting at a conference table, smiling, with nameplates labeled 'PANELIST' and 'CHAIR', microphones, papers, and water glasses in front of them, in a wood-paneled conference room.

    UN Working Group on Firearms panel presentation on arms embargoes and the destruction of surplus stockpiles

    Vienna, April 29, 2025

    Read more
  • Two people sitting at a table during a conference with a backdrop displaying the American Society of International Law. The woman on the left has shoulder-length brown hair and is wearing a black blazer with embroidery, and the man on the right has short dark hair, glasses, and is dressed in a suit with a tie. They have microphones and water bottles in front of them.

    American Society of International Law, 119th Annual Meeting — Hague Closing Plenary: 'Can Arms Trade Bring About Peace?'

    Washington D.C., April 18, 2025

    Watch now
  • A man in a grey suit giving a speech at a podium with the Swiss flag emblem during a formal meeting. Several people are seated and listening, some in military attire. A large screen is in the background.

    International Forum on Trafficking and Diversion of Firearms in Latin America

    Mexico City, February 25, 2025

    Watch now
  • León Castellanos-Jankiewicz delivers a presentation at the conference on The Business of Lethality held in El Colegio de México on November 4, 2022.

    UN Working Group on Firearms panel presentation on accountability of private security companies

    Vienna, April 4, 2024

    Read more
  • León Castellanos-Jankiewicz delivers a speech at the UN Constructive Dialogue on Firearms in Vienna on May 5, 2023.

    Statement on EU due diligence at the UN Constructive Dialogue on Firearms

    Vienna, May 5, 2023

    Read more
  • León Castellanos-Jankiewicz in dialogue with Alejandro Celorio Alcántara, Principal Legal Advisor of the Mexican Ministry of Foreign Affairs.

    Expert Roundtable on Transnational Civil Litigation and Corporate Liability: Mexico v Smith & Wesson

    The Hague, May 2, 2022

    Read more

Contact

Email

L.castellanos@asser.nl

Twitter/X

https://x.com/leoncastjan

Address

Asser Institute for Internatonal and European Law

R.J. Schimmelpennincklaan 20-22

2517 JN, The Hague

The Netherlands