Defending Before the International Criminal Tribunal for the Former Yugoslavia
An Interview with Colleen Rohan
Edited by Cailan Cumming, Kate Gibson & Paul R. R. Williams
A Note on Defending Justice
This blog is part of the Defending Justice series, an initiative of the Public International Law & Policy Group (PILPG) to promote an eclectic array of voices within the field of international criminal law.
As part of our broader efforts to strengthen institutions of justice, this series seeks to create space for dialogue around the varied perspectives and concerns that shape these institutions. With that aim in mind, we interviewed a series of defense practitioners working in international criminal law and distilled their experiences and insights into a series of first-person blogsblogs, preserving the spirit and voice of those interviews.
Editor’s Note
This blog presents the experiences and perspectives of Colleen Rohan, a prominent defense lawyer whose decades of defense practice encompass some of the toughest cases in U.S. domestic criminal law as well as landmark cases before the International Criminal Tribunal for the former Yugoslavia (ICTY). Through her personal journey in international criminal law, Rohan offers a singular perspective on the evolution of international defense, including the creation of the Association of Defence Counsel (ADC), the practical and ethical questions of representing persons accused of serious international crimes, and the procedural and institutional obstacles that shaped the early operations of the ICTY. Drawing upon Rohan’s experiences, readers gain insight into the daily realities of defense work, from navigating disclosure battles to fostering collegiality in a multicultural defense community, to the ways in which defense counsel must adapt to evolving legal systems. Her experiences illuminate both the successes and limitations of the ICTY, the development of substantive international criminal law, and the ongoing need for recognition, resources, and respect for defense practitioners in international tribunals.
Introduction
When the International Criminal Tribunal for the former Yugoslavia (ICTY) was established in 1993, it was in response to atrocities that shocked the world—mass killings, ethnic cleansing, systematic rape, and the genocide in Srebrenica. For the first time since Nuremberg, an international court was created to hold individuals accountable for war crimes, crimes against humanity, and genocide. Over the years, the tribunal indicted political leaders, military commanders, and others in positions of authority, setting important precedents in international criminal law while also drawing criticism for its accessibility and procedures.
By the time I arrived in The Hague, the tribunal had already been operating for more than a decade, but my own journey there had begun much earlier. I never set out to become a lawyer, let alone an international criminal defense lawyer. As an undergraduate at UC Berkeley, in Berkeley, California U.S. I worked to support myself, taking a job as a typist at the Meiklejohn Civil Liberties Institute under Ann Fagan Ginger, a remarkable human rights lawyer. I thought I was headed toward a career in psychology, but Ann pushed me to consider law. I then worked as a typist for Patrick Hallinan, a celebrated criminal defense lawyer in San Francisco, where I was taken to court and given real work to do. Patrick also encouraged me to go to law school and told me he would give me a job if I did, which he followed through on. These two mentors, who convinced me that law would be a way to help people, were instrumental in my beginnings in law.
My journey into law was a gradual process, but I was fortunate to be part of a generation that believed lawyers were not simply there to earn a fee, but to use the law as a tool for positive change in people’s lives. We genuinely felt we could help shape the law while helping individuals. We were not naïve, but we were optimistic, an optimism that waned as our legal careers progressed. Still, that early sense of altruism was essential in driving us forward as young lawyers.
My first introduction to ‘international’ law was when Patrick Hallinan was engaged to represent an American, William Joseph Quinn, who traveled to Ireland to join the Irish Republican Army (IRA) and was charged with a series of bombings in England and for the murder of a police officer in London. Watching that case unfold, with questions of extradition and about laws in other countries, opened my eyes to a field of law I had not considered before. Still, I spent the next 25 years in the U.S., first in private practice, later at the State Public Defender’s Office handling serious felonies and death penalty cases, and then back in private practice defending gang cases and post-conviction death penalty cases.
In the late 1990s, my partner Gregor Guy-Smith, also a defense lawyer, and I moved to Toulouse, France. While there, we followed the developments of the international tribunals for Rwanda and the former Yugoslavia. Given our background in criminal defense, they struck us as interesting places to work and as a way to stay in Europe. Though we eventually returned to the United States, the seed had been planted.
At that time, there was a small but growing community of lawyers involved in international criminal law. Gregor attended a meeting of these lawyers in Montreal where he met Peter Murphy, who was working on the first Kosovo case at the ICTY against Fatmir Limaj, Isak Musliu, and Haradin Bala, members of the Kosovo Liberation Army (KLA) who were charged and later acquitted of war crimes. Peter invited Gregor to join the defense team for Haradin Bala, and eventually Gregor became lead counsel.
I spent time between California and The Hague, as our daughter was still in high school, but I met many people in the Hague community. Eventually the Registrar suggested that I take on cases myself, considering me qualified and recognizing the need for defense counsel at the time. After nearly 25 years in domestic criminal defence I formally entered the world of international criminal law.
Both Gregor and I were deeply interested in the development of international criminal law, the kind of law that was being practiced, which was very different from U.S. domestic law, and the future of these tribunals. Life in The Hague meant being part of a vibrant, dynamic community with constant intellectual discussion about the law. We quickly realized how much there was to learn and how trials operated in other countries. Many who left The Hague to return to domestic practice often came back due to just how compelling this field of law was. For us, the transition into international criminal law ultimately felt natural, meaningful, and engaging.
First Case
My first case at the ICTY was representing Milorad Trbic, a Serb implicated in the genocide in Srebrenica. I arrived in The Hague early that first morning, and by 11 a.m., I had my first meeting with the Prosecutor. He briefed me on the case and handed me three large boxes of disclosure, which was just the beginning of what would eventually amount to hundreds of thousands of documents. By the end of the case, even after I had moved on, over a million documents had been disclosed.
After the meeting, I went to the ICTY’s ‘Defence room’. It was a shared space with a few computers and desks, but all the defense teams at the tribunal needed to use this space, which was about 30 to 40 people. With so few resources and no offices, there was constant jockeying for space and equipment. Most of the defense team members were from Serbia or other parts of the former Yugoslavia, and many different languages filled the room. At first, I felt completely overwhelmed. Setting up an office and figuring out how to begin going through the case was mostly up to me at this time.
A woman introduced herself as co-counsel for one of the co-accused in the Srebrenica case. She told me there were many things I did not know because the case had progressed before my client was arrested and indicted and before I was brought in as counsel. She then proceeded to tell me that my client had confessed to 26 murders he did not commit and that his confession was false. This revelation completely shifted how I approached the case and evaluated the disclosure before even meeting my client. In my entire career as a defense lawyer I had never experienced anything like that—a false confession to 26 murders.
My co-counsel’s experience and local knowledge of the region and the war were invaluable. What could have been an intimidating first day instead became an important and welcoming introduction to the international defense community. I quickly realized that the collegiality among defense lawyers was strong and was a vital support system in navigating my first case.
My first day in court was equally eye-opening. I had to wear a robe, use headphones for translation, and navigate multiple computer screens for simultaneous interpretation. The proceedings involved three judges and no jury—a clear difference from my experience in the U.S. common law system. I had no time to thoroughly prepare so I relied on advice from colleagues who had gone through the same experience in order to understand exactly what to do in court. In other aspects it was easier for those coming from a common law system to learn the tribunal’s legal system. Many of the defense lawyers came from Serbia, a civil law system, without adversarial procedures like cross-examination, so even seasoned lawyers from these systems needed to learn courtroom techniques that were specific to the tribunal. That was a lot of pressure and challenge in such a high-stakes environment.
Other aspects of the system were not so comfortable to me as someone coming from a common law system. Hearsay evidence was admissible, certain witnesses were protected and inaccessible, and client access could also be difficult. Gradually, we adapted to the rules and procedures while working on our case and observing other cases, even if we did not like the rules and procedures we had to work with. One of the aspects of working at the tribunal that I never quite got used to was navigating the relationship with the prosecution. In the U.S., regardless of your relationship with the prosecutors, they will generally provide the required information, be reasonable, and generally be collegial. At the ICTY, some prosecutors seemed reluctant to share relevant or exculpatory evidence and at times could even be considered hostile towards the defense. The ICTY itself was structured around three pillars—Registry, Judges, and Prosecution—and as defense counsel, we were not formally part of this hierarchy. This meant the prosecution could sometimes view the defense as a necessary obstacle to be dealt with at trial.
That first case taught me the realities of international criminal defense: navigating an unfamiliar legal system, managing massive disclosure with limited resources, and building relationships within a complex institutional structure, all while advocating for a client whose liberty and life were at stake.
Ethics of Defense Representation
In the United States, much of my early career was spent handling gang-related cases, including death penalty work. These cases could be quite demoralizing as they involved deeply damaged victims, deeply damaged clients, and often involved individuals who were emotionally and mentally unstable and had committed cruel and vicious crimes. The negativity was unrelenting. Over time, it took a toll.
Given the gravity of the crimes tried at international tribunals, many people assume that the ethical questions of defending clients at international tribunals must be even greater. In fact, I found the opposite to be true. My clients at the ICTY were not gang members or career criminals but rather those working in the military or members of the political structure. They were men who had once lived what we might call ordinary lives—people with an education, with families, with stable homes—until the war broke out. The only reason they became involved in criminal conduct was because the war literally arrived at their front doors. They were fighting for their communities, their families, and for what they believed in, in the context of a violent, ongoing war. If it was not for the war these people probably, with rare exception, would have never committed a crime.
Take someone like Milorad Trbić, a low-ranking officer in the Bosnian Serb Army. He was trained, above all else, to follow orders. In military life, obedience is non-negotiable. Today, we have rules of law prohibiting soldiers from carrying out commands that are facially illegal or immoral, but in the reality of war, that was not the case for many of the officers on the ground. Many of the people who were told to shoot civilians in Srebrenica said no, and there was a whole regiment whose leader refused to shoot civilians, and they walked away. Some are able to withstand the pressure of those commands in a military environment. Others are not.
In the U.S., I represented people who often made destructive choices in their everyday lives. At The Hague, many of my clients were men who did not generate the situation that brought about the crime, but rather the situation was generated for them. These were men who would never have committed a crime had it not been for the war. For me, there was never an ethical conflict in defending someone who had been put in such a situation. Now, that is an entirely separate issue from whether they have a proper defense or not.
Other defendants came from the political leadership. I was on the standby team for Radovan Karadžić, who, as President of the Republika Srpska, was prosecuted for nearly every crime committed during the war. Karadžić was highly educated and highly intelligent. You may completely disagree with his worldview—and I certainly did—but like anyone involved in war, he took day to day decisions about the battlefield, and he did so with others who were in the political structure. Leaders on all sides were responding to very real political issues.
To understand that dynamic, you need to go back to the history. All wars, including the war in the former Yugoslavia, are in response to something. For instance, Bosnia’s former Muslim president, Alija Izetbegović, had published The Islamic Declaration in 1970, which Serb leaders interpreted as a call to transform Bosnia into a Muslim state. So, when Muslims moved into the area, they felt threatened, and tension and hatred began to build. When you combine this tension with the reality of war where people have lost their homes and family members; cannot work; and cannot walk anywhere without feeling unsafe, you begin to understand where the sense of existential threat comes from and how people are driven or feel driven to make decisions that we would not take under normal circumstances. Under those conditions, decisions were made that, in hindsight, absolutely constitute war crimes. How much of that is understood at the time is another complex issue.
This is why learning about your client’s history, culture, and lived reality is absolutely essential in international criminal defense. Whenever possible, I tried to travel to the region, meet people, and attempt to understand what it must have been like for my client during the war. Through this exercise, you can begin to understand why your client functioned the way that they did—not to excuse their behavior but to attempt to understand it. Defendants make poor choices and may be racist or Islamophobic, but these things never raised a single ethical barrier for me in representing them. My role was not to endorse their views, but to test whether they were guilty of the alleged crimes under the law, to ensure their rights as defendants were respected, and that they received a fair trial.
At the ICTY, we also had the Association of Defence Counsel (ADC), which I will discuss in greater detail below. The ADC was a professional association of defense counsel working at the tribunal and it included a disciplinary committee. This body was there to support lawyers who faced genuine ethical dilemmas in their cases and did not know how to resolve them. The committee could provide confidential advice and opinions, helping counsel navigate the complexities of international criminal practice. That structure itself was a recognition that, in this unique environment, ethical questions could arise in ways we might not encounter in domestic practice.
Shaping the Future of Defense
The Birth and Development of the ADC
When I first arrived at the ICTY, it quickly became clear that very little thought had been given to the defense during the tribunal’s creation—who we would be, how we would be supported, how we would fit into the institution, or how we would function. The tribunal paid us to handle our cases, but beyond that, we were largely on our own.
In the early years, defense counsel were highly restricted and, in many ways, ignored. For example, our badges allowed us to enter only a narrow corridor leading to the defense room in the tribunal building. We were barred from the cafeteria, the library, and certainly from entering the Prosecutors’ offices. Meanwhile, the prosecution had full offices, support staff, and access to a database of cases and case law that we could only consult from within the building. For those of us not living full-time in The Hague, legal research was incredibly difficult. We were permitted just three paid travel days to the Hague per month unless our case was in trial, which meant that the lawyers who did not live in the Hague full-time could not conduct legal research for their cases.
At one point the Judges became concerned about the ethical practices among defense counsel. They proposed creating a structure to monitor ethical behavior and provide training. Many of us thought this was an excellent idea because at least, finally, we were being included in the institution in some way. Based on this original group, and working closely with the Registrar, we established what became the Association of Defence Counsel (the ADC or ADC-ICTY).
The ADC was a proper association, complete with a constitution, executive committee, president, training committees, and a disciplinary committee. It was the first step in providing the basic support that defense counsel needed to prepare and defend their cases effectively. By 2005, new defense counsel could walk into the tribunal building, knock on the door of the ADC, and receive the minimum guidance, information, and access necessary to do their work in this new environment.
Within a couple of years, the ADC began offering trainings with the basic information needed for defense counsel to do their jobs, such as how to conduct direct and cross-examinations, and substantive training on international criminal law. This was essential because the ICTY was the first modern international criminal tribunal, meaning many legal issues were being determined in real time and international law was constantly evolving. At the time you could not access this information on your home computer so the ADC’s trainings were critical.
The community support that grew from the ADC was invaluable. Defense counsel came from all over the world, including countries that had once been on opposite sides of conflicts, yet we shared a common language: going to court and representing the accused. Overcoming these early challenges together forged a strong bond among us. Working together to do our job effectively became more important than any of our differences.
Looking back, the birth and development of the ADC was one of the ICTY’s most enduring contributions to the international defence community. The ADC has now existed for over twenty years, and its legacy paved the way for the ICC’s Defence Association, the ICCBA, which gives defense counsel similar institutional support after many years without it.
Manual on International Criminal Defence
When the ICTY began planning to put out a manual to explain the basics of the tribunal and its three pillars of the Chambers, Prosecution, and Registry, the Office of the President suggested that someone write a chapter about the Defense. I wrote the chapter and included commentary on some of the challenges we faced as defense counsel, particularly regarding limited resources and difficulties in securing disclosure from the prosecution. Those who initially read the draft described it as reasonable and constructive. However, the Prosecution was not pleased. They wanted the sections on disclosure challenges removed. In the end, the ICTY President’s office did not allow us to edit the chapter and simply left it out of the final manual.
The primary funder of the manual, the United Nations Interregional Crime and Justice Research Institute (UNICRI), seeing that the defense chapter had been taken out, asked if the ADC would be willing to put together a defense manual for publication. We agreed. Lawyers from the ICTY, coming from all over the world, contributed to the manual, offering practical guidance on every aspect of defence work—from conducting direct and cross-examinations to writing and arguing motions, to interviewing witnesses effectively.
The publication of that manual marked a turning point. The perception of the ICTY judges towards the defense began to change. They started to recognize the defense’s role within the tribunal and the value of our inclusion in tribunal matters, rather than just limiting our relevance to basic due process rights. Defense representatives were now invited to important meetings and we felt that our role was more respected, our ideas listened to, and that we were treated with less hostility.
In the early days of the ICTY, for example, the defense was rarely consulted or listened to by the Rules Committee, which decided on changes to rules and evidence procedures that directly affected our daily work. Often rules were passed without considering how they would function from a defence perspective, which meant wasted time and resources litigating adjustments that could have been avoided with proper consultation. The manual, and our advocacy in creating it, helped change that dynamic, giving defence counsel a stronger voice and greater accessibility within the tribunal.
Legacy of the ICTY
Fairness of Trials
When I reflect on the trials at the ICTY, I believe that, by and large, they were fair. Admittedly, at the beginning, I approached the proceedings with some skepticism, assuming that judges might be biased. But in practice, I found most of them were genuinely trying to reach reasonable conclusions based on the evidence before them. There were, of course, exceptions where judges made their bias absolutely clear. One well-known case involved Judge Frederik Harhoff, whose impartiality was called into serious question after he sent a private email to a large group in which he was critical of his judicial colleagues’ judgments acquitting certain commanders, and expressed his view the acquittals were political and did not follow the law. He was subsequently removed from the tribunal.
In my own cases, I found the judges made an effort to adhere to the rules of evidence and procedure. Appearing before a panel of Judges is a completely different experience from presenting your case to a jury. In an international tribunal like the ICTY, you are building a working relationship with three individuals who are deciding a case and it is very different from the relationship you have with a jury. It is not about appealing to the emotions of a jury but rather about establishing credibility with the judges, demonstrating the reliability of your evidence, and presenting yourself as a trustworthy advocate. You are trying to figure out who the judges are and how they think. Through that process you hope that they will listen to you and accept your view of the evidence.
Development of International Criminal Law
In terms of the broader development of international criminal law, I believe the ICTY had an enormously positive impact, provided people actually pay attention to it. I do not agree with every decision that came out of the tribunal, but the parties and the Judges worked through some extremely complex factual and legal questions. They produced opinions that can be relied upon in later courts and tribunals, creating a body of jurisprudence that continues to influence international criminal law. The challenge, of course, is that no one is formally required to follow ICTY decisions, but they are cited, studied, and increasingly used as a reference. Domestic courts and specialized tribunals in the region, such as the War Crimes Chamber of the Court of Bosnia and Herzegovina and the European Union Rule of Law Mission in Kosovo (EULEX), have drawn on ICTY jurisprudence to guide their own proceedings.
International criminal law is, and will always be, a dynamic and evolving field. In my view, the ICTY played a critical role in shaping this landscape, setting standards and offering a foundation upon which future tribunals and courts built upon and continue to build upon.
Continuing Challenges
When I look at the landscape of international criminal law today, I see both progress and lingering challenges. Compared to the ICC, I believe the ICTY had a particularly strong defense association, and over time, we gained much better recognition of the defense’s role and function within the tribunal. That recognition, however, does not remove enduring issues, particularly when it comes to disclosure of exculpatory evidence, an issue that has major implications on the right to a fair trial.
Disclosure was a significant challenge at the ICTY, and it continues to be at the ICC. I recall one case at the ICTY where we actually filed a motion seeking sanctions against a Prosecutor for withholding exculpatory evidence. The Trial Chamber granted our motion and ordered sanctions, but on appeal, the decision was overturned. The Appeals Chamber was concerned about setting a precedent that would hold a Prosecutor personally accountable in this way. In another case, I remember a particularly sympathetic witness—an older gentleman who spoke about the brutal killing of his parents and how the war had devastated his life. He spoke about who he thought was responsible for the human cost of war and who he thought directed it, and he left the courtroom as a highly credible witness. A few days later, however, we received a late disclosure from the prosecution: this same witness was actually a wanted war criminal and had committed crimes against humanity himself. By the time this information came to light, he was no longer available for cross-examination. The late disclosure fundamentally affected the fairness of the proceedings, leaving us unable to properly examine or challenge his statements.
At the ICC, there are similar, and in some respects, more structural challenges for the defense. One example is the delayed admissibility of evidence. At the ICC, the admissibility of all evidence that the parties seek to admit and present during the trial is only formally ruled on by the judges at the end of the case. This means that if the Prosecutor seeks to admit an expert report and the defense objects, arguing that it is inadmissible on certain grounds, we will not know during the trial whether the evidence will ultimately be accepted. This makes it impossible for a Prosecutor to know if they have met their burden of proof. For the defense, this creates a major dilemma: we cannot determine whether we need to present affirmative evidence to rebut certain claims. Essentially, we are left guessing, which is unfair and undermines the defendant’s right to a fair trial.
Conclusion
Reflecting on my experience, I would emphasize the importance of cautious optimism for young lawyers entering the field. When I first began practicing at the ICTY, the dynamism of international criminal law, combined with the diverse and supportive community of defense counsel, was what drew many of us to The Hague and continues to bring lawyers back today. Learning from other defense counsel how to navigate a new court system, and learning as you go on each case, continues to be a vital part of practicing defense in international tribunals.
The existence of a Defence Association, first at the ICTY and now at the ICC, remains crucial for onboarding and basic training of defense lawyers, providing guidance and support in a complex and often overwhelming environment. Yet challenges remain: limitations in technology, inadequate facilities, and restricted funds for travel all continue to impact the effectiveness of the defense.
Despite these challenges, the defense community at the ICTY overcame these obstacles together, forging strong bonds across cultures and legal traditions, a practice that continues today at the ICC and other international tribunals. As the first modern international criminal tribunal, the ICTY faced constant legal evolution, and both Counsel and Judges worked hard to address extraordinarily complex issues. From my perspective, the ICTY made a tremendously positive contribution to the development of substantive international criminal law, producing solid jurisprudence that continues to guide courts and tribunals around the world. The creation of the Association of Defence Counsel (ADC) was also a critical achievement, ensuring that defense voices began to be recognized and supported.
Looking forward, international tribunals must continue to build on these lessons. Proper funding and resources, clear communication, a strong defense association, and genuine recognition of the function of the defense are essential for maintaining the fairness and integrity of international justice. Counsel must be included in discussions regarding rules of procedure, and the prosecution must be held to high standards of timely and full disclosure of exculpatory evidence. Ultimately, even as decades pass and new tribunals are created, the needs of defense practitioners remain the same: for our role to be recognized, our ideas heard, to be treated with respect, and that our basic needs are met so that we can effectively represent our clients. The ICTY was one important step toward achieving this and advancing true justice before the eyes of the international community.

