Their pact started as a bit of a lark. Though the Philip C. Jessup International Law Moot Court Competition was born at Harvard Law School in 1960, the school had never won the world championship. So, the 2022 Harvard Law School team vowed to get matching Jessup tattoos if they took home the top prize. 

In April 2022, Harvard Law School prevailed over 700 teams from 85 countries and walked off with the Jessup World Cup for the first time. True to their word, Marta Canneri ’22 — who was named best oralist in the final round — and Hannah Sweeney ’24 headed out the next day to a tattoo parlor on Massachusetts Ave in Cambridge for a permanent tribute now inked onto their triceps. A few weeks later, two other team members, Katherine Shen ’22 and Nanami Hirata ’23, also got Jessup tattoos.

“It was an inside joke,” explains Sweeney, “because a major principle of international law is Pacta sunt servanda” — literally, agreements must be kept and states are bound by their promises. “Thus our agreement to get tattoos must be kept.”

The tattoos are colorful evidence of just how central Jessup becomes to the lives of those who compete. The largest moot court competition in the world, Jessup simulates a fictional dispute between two countries argued before the International Court of Justice, the principal judicial organ of the United Nations. Each year, approximately 700 teams from around the world are presented with a timely problem of international import, each team dedicating hundreds of hours in research, brief writing, and oral advocacy practice preparing for the competition in the spring.

The experience not only sharpens intellectual and practice skills, but fosters a close-knit community among teams, their coaches, and advisers. Over the past six decades, Harvard Law students, faculty, and alumni have been deeply involved in all facets of the event, from competing to coaching to serving as judges to writing the annual Jessup problem.

This year, Sweeney and Hirata are again competing (the others on the championship team, including Stephanie Gullo ’22, graduated last year) and so far, they are doing very well. In March, the 2023 team — which also includes Ariq Hatibie ’24, Nick Caputo ‘24, and Yen Ba Vu ’24 — took second place in the New York regionals and won best overall written memorial. They will be defending the championship in the 2023 White & Case Jessup International Rounds, on April 8-13, in Washington, D.C., which marks the first time international rounds will be held in person since before the global pandemic pushed the competition online.

“Statistically we are not likely to win again. But we do it because it’s worth it for the friendship and professional growth,” says Sweeney, who plans a career in public international law. “Jessup is very clearly the best thing that has happened to me at HLS. It has been the most invaluable part of my legal education.” And, like so many Jessup alumni, after graduation, she plans to “continue to judge/coach future Jessup rounds indefinitely,” she says.

“Jessup is very clearly the best thing that has happened to me at HLS. It has been the most invaluable part of my legal education.”

Hannah Sweeney ’24, member of Harvard Law School’s 2022 Philip C. Jessup International Law Moot Court Team – U.S. National and World Champions

“One thing I’ve always found very impressive is that the students involved from four or five or six years ago are still extremely interested and invested in how the team does,” says Andrew B. Loewenstein, an expert in public international law at Foley Hoag who has advised the Harvard Law team since 2018. “They come back and serve as practice judges or are cheering from afar, so it’s a terrific way for alumni involved in this very seminal experience to continue to be engaged with the people who are their successors.”

“When you talk to a Jessup person, even if you never knew them before, they very quickly become a very good friend,” says Xuejiao “Katniss” Li LL.M ’23 — a big fan of “The Hunger Games” — who adds that Jessup is “one of the most important things in my life.” Li participated for five years in China, including while getting her master’s degree in law, during which she was named national champion and won best oralist and best memorandum. As an LL.M student at Harvard this year, she was a judge of the Chinese rounds — in which 61 schools participated via Zoom — and she was also a judge for the D.C. regionals of the U.S. competition, which did not include Harvard Law.

“Jessup will allow you to think creatively” no matter the particulars of the moot problem, says Li, who plans a career in international law. “Most of the time you can’t find [answers] in the textbooks. It’s your imagination, your attitude toward the world [that] will allow you to solve challenging problems facing the world.”

Friendly beginnings

The Philip C. Jessup International Law Moot Court Competition, originally called the International Law Moot, started as a friendly competition among four Harvard Law School students — two Americans and two international students — to explore a timely question of international law through a simulated oral argument before the International Criminal of Justice. It was the brainchild of longtime Harvard Law Professor Richard R. Baxter ‘48, who collaborated with Professor Stephen M. Schwebel Harvard College A.B. ’50, later an ICJ judge, to create the event.

The Jessup Competition, originally called the International Law Moot, started as a friendly competition among four Harvard Law School students — two Americans and two international students — to explore a timely question of international law.

The first event took place at Harvard Law School on May 8, 1960, with Thomas J. Farer ’61 and William Zabel ’61 representing the U.S. against two LL.M. students, Ivan L. Head LL.M. ’60, a Canadian student who would later become a foreign policy adviser to Canadian Prime Minister Pierre Trudeau, and Bernard H. Clark LL.M. ‘60 of New Zealand. Their problem, “Cuban Agrarian Reform Case,” was written by Schwebel, and final round judges included Harvard Law Professor Roger Fisher ’48, a pioneer in the field of international law and co-founder of the Harvard Negotiation Project, and Milton Katz ’31, former administrator of the United States Marshall Plan in Europe, who taught international law at Harvard.

“It was exciting, it was brand new, and the more interesting question to me is how we got picked,” recalls Zabel, laughing, “because we didn’t have any particular knowledge or expertise in international law, and also we were so young. I guess they did it because of our debate history.” As undergraduates at Princeton, Zabel and Farer served together on the Princeton debate team. That first Harvard Law competition, in which no winners or losers were declared, was “mostly fun,” adds Zabel, and though he only participated once, it spurred his interest in international law, since “there weren’t many ways to get involved in international law in those days.”

Zabel was an associate at the international law firm Cleary Gottlieb before forming his own firm, where he built a storied career in international human rights and civil rights, including writing the amicus brief for the ACLU in Loving v. Virginia, in which the U.S. Supreme Court in 1967 declared anti-miscegenation laws unconstitutional. Still active in law practice, he says he doesn’t remember much more about the birth of Jessup. “It’s just so long ago, I’m happy to be alive to talk to you about this,” Zabel says, again laughing. “But you can certainly say Tom and I gave it our all. If we had flopped it might never have continued.”

Farer, who served for years as dean of the Josef Korbel School of International Studies at the University of Denver, where he continues to teach human rights and U.S. foreign policy, also has fond memories. “Since I loved to debate and had been very successful [at it], and since I liked Bill and because I was interested in things international, of course I was going to do it, and the topic interested me,” says Farer, who also served as president of the Inter-American Commission on Human Rights. “I was very interested in Cuba and Castro, and I think we defended the position that Castro’s confiscation of U.S. property was a violation of international law, but I would have been quite happy with either side of the issue. The topic was ripe and I thought it would just be fun, and it was fun.”

In the 1963 competition, champions were declared for the first time. In 1968, the competition was opened to non-American teams, and Baxter, the first holder of the Manley Hudson Chair of International Law at Harvard Law School and later a judge on the ICJ, renamed it the Philip C. Jessup International Law Moot Court Competition in honor of the diplomat and international law expert who served for years on the ICJ. (The Jessup Competition includes an annual award for excellence in writing named in Baxter’s honor.)

Clark and Head are no longer alive. But Jessup has grown into an enormous worldwide event, with many Harvard Law alumni and faculty deeply involved over the years: David J. Barron ’94, a judge on the U.S. Court of Appeals for the First Circuit and the Louis D. Brandeis Visiting Professor of Law, was among the authors of the 2009 Jessup problem, or Compromis, as it’s known. Amir Farhadi LL.M ’18, who was a member of the Jessup Team at Sciences Po Law School in Paris, France that won the 2016 French National Championship, co-authored the problem used in the 2020 competition. Farhadi now works on ICJ cases with Loewenstein at Foley Hoag and continues to assist the HLS team with practice rounds. 

Jessup has long presented an opportunity for J.D. and LL.M. students to collaborate with each other. Shayan Khan LL.M. ’22, who participated in Jessup’s international rounds during his LL.B. studies in Pakistan, coached the 2022 championship team along with team advisers Maria Laura Pessarini LL.M. ’22 and Loewenstein. And Peter L. Murray ’67, a visiting law professor at Harvard, taught a tailored workshop for the team, Oral Argument Before International Tribunals.

Last year’s problem involved disinformation and the freedom of expression, botnet takedowns, the secession of part of a nation’s territory, and foreign election interference. Team members cited the course “Public International Law,” taught by Professor Gabriella Blum LL.M. ’01 S.J.D. ’03, as laying a strong foundation for researching the issues that arose in the case. And in addition to Blum, says Sweeney, professors in other international law classes she’s taken have been very helpful including Naz K. Modirzadeh ’02, founding director of the Harvard Law School Program on International Law and Armed Conflict, and visiting professor Ioannis Kalpouzos, who specializes in public international law.

The competition, which is administered by the International Law Students Association, “has shaped my entire career goals,” says Sweeney. “Before I entered law school, I was not entirely sure what public international law litigation looked like in practice. I found the answer in Jessup.”

This year, the Harvard Law School team is coached by Sagnik Das LL.M. ’19, who is currently an S.J.D. student, along with Loewenstein. The Compromis involves the interpretation of a peace treaty, deadly attacks in allegedly occupied territory, unilateral economic sanctions, and the legal consequences of failing to dispose of hazardous waste properly. In the fall, team members spent roughly 10 to 15 hours a week working on research and written memorials, says Sweeney, and over January term they worked almost full-time on the written memorials. In the spring, they practice roughly 20 hours a week, and while at competitions, they miss class for a week and moot full-time every day. “It is a lot of work and certainly only makes sense for Public International Law nerds who are truly passionate about international law,” says Sweeney.

“I think the central value is that it forces students to engage deeply with a very complicated set of factual legal problems where there is no clear-cut answer, so it really compels students to develop their advocacy skills because it’s not like they can just look up the answer somewhere,” says Loewenstein. “It’s a phenomenal way to prepare for actual legal practice,” whether in international law or not.

“I truly think they are some of the most incredible legal minds I’ll meet here — and probably anywhere — and are most importantly so compassionate and fun to be around,” says Hatibie, who is on the 2023 team. “It’s nice to find a group, indeed a community — shout-out to all the professors and LL.M.s who have taken the time to judge us — that embraces the world and is committed to the prospect of changing it for the better, using the common language of international law.”

Loewenstein says all the HLS teams he’s worked with were “uniformly excellent.” Still, he adds, “There was something special about the team last year. I think it was just the absolute dedication to really understanding the subject matter and putting in the time and effort, and also just the kind of innovative legal advocacy skills that all of them had in spades.” Jessup “really forces students to cooperate and engage with each other in a way that enhances everybody’s abilities,” he adds. “I think last year’s team did that particularly well.” “It is truly a life-changing program,” says Sweeney, and — as her tattoo attests, “a life-long commitment.”

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