Legacy website of the International Criminal Tribunal for the former Yugoslavia

Since the ICTY’s closure on 31 December 2017, the Mechanism maintains this website as part of its mission to preserve and promote the legacy of the UN International Criminal Tribunals.

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The success of trials held before the Tribunal depends greatly on the willingness of witnesses to come to the Tribunal to testify. Witnesses help to establish the facts of crimes with which the accused are charged, thus contributing to the process which establishes the responsibility of the accused and creates a historical record of what happened during the conflicts in the former Yugoslavia.

Several thousand witnesses have come before the Tribunal to tell their stories or share their expertise. In doing so, they have helped the Tribunal’s judges to render justice and establish the truth.

Different groups of witnesses testify before the Tribunal

Victim or survivor witnesses

The majority of witnesses who have come before the Tribunal are people who survived crimes, who witnessed them, or whose family members were victims of crimes. Many of them still suffer physical and psychological trauma from the horror that they lived through. For these people, the act of testifying is an extremely courageous one.

Testimonies of witnesses describe war-related experiences, such as extreme deprivation of food, health-care and safety; destruction of home and community; separation and disappearances of family members; severe beatings and physical torture; sexual violence and rape; abuse, torture and killing of others; perilous flight or escape and forced exile.

Even though testifying before the Tribunal may be a difficult and painful experience, witnesses are often motivated to speak for the dead, to tell the world the truth about what happened and to look for justice in the present in the hope that such crimes will not happen again.

“Insider” witnesses

Many of the Tribunal’s accused are high-level political, military or police leaders who are charged with planning crimes and ordering others to commit them. Persons who were close to the accused, called “insider witnesses,” can provide the court with evidence about their actions and state of mind. The evidence gained from their testimony is often crucial for the establishing the degree of responsibility of the accused.

Perpetrator witnesses

A number of those accused by the Tribunal pleaded guilty to all or some of the crimes with which they were charged, and agreed to testify for the prosecution and help the court to establish the truth. These witnesses provide a unique insight into how political, police and military leaders planned and committed crimes on a massive scale.

Expert witnesses

These witnesses are professionals who provide their expert opinion on topics such as military doctrine, political structures, former Yugoslav law, demographics, financial transactions, and forensic evidence. They help the judges to determine the circumstances in which crimes were committed, the accused’s authority over their subordinates, the identity and number of victims found in mass graves, the number of victims killed in an area, among others.

Support for witnesses

The Tribunal is committed to supporting all witnesses who come before the Tribunal to testify. The Tribunal has a special unit—the Victims and Witnesses Section (VWS)—dedicated to supporting and protecting all witnesses, whether they are called by the prosecution, defence or chambers. This independent and neutral body provides all the logistical, psychological and protective measures necessary to make their experience testifying as safe and as comfortable as possible.

The Tribunal is particularly mindful of the fact that testifying about the war related events can be difficult for the witnesses. The Victims and Witnesses Section has trained professional staff, available on a 24 hour shift basis that can help witnesses with their psycho-social and practical needs before, during and after their testimony in The Hague. In close cooperation with the VWS in The Hague, the Sarajevo Field office responds to all requests for assistance in the territories of the Former Yugoslavia.

The VWS develops its principles, policies and procedures to ensure that all witnesses can testify in safety and security, and the experience of testifying does not result in further harm, suffering or traumatisation to the witness. The VWS fosters an environment in which testifying can be experienced as a positive, strengthening and enriching event.

The VWS is divided into two separate entities. Firstly, two teams consisting of Support and Operational staff deal with support and logistical issues. Their focus is on the provision of social and psychological counselling and practical assistance to witnesses, as well as logistical operations and witness administration. Secondly, the Protection Unit coordinates responses to the security requirements of witnesses.

The VWS operates with the highest levels of integrity, impartiality and confidentiality, and ensures that all witnesses are informed about the rights and entitlements and have equitable access to the services of the section.


Witness Protection Measures

The majority of witnesses who testify at the Tribunal do so in open court. However, if they feel it is necessary to protect the witness’ security or privacy, the prosecution and defense can ask the court to apply protective measures. These measures are enshrined in the Tribunal’s Rules of Procedure and Evidence (Rule 75 and Rule 79) and allow:

• Taking the witness’ name and/or identifying information off the Tribunal’s public record
• Modifying the image of the witness’ face and/or voice in televised proceedings
• Assigning the witness a pseudonym
• Allowing the witness to testify in closed session
• Allowing the witness to testify remotely via video

These measures are aimed at minimising the risks to witness’ safety as a result of testifying. Although all present parties in the court know the witness’ identity, they are bound by the law and judges’ orders to respect the measures and protect the witness’s identity accordingly. In case any party would disclose the identity or any other identifying information of a protected witness, this party could be held in contempt of the Tribunal and be liable to a maximum penalty of 100,000 Euros, or a term of imprisonment of seven years or both.


Responsibilities of witnesses

Witnesses appearing before the Tribunal also have responsibilities and are required to make a solemn declaration before they begin their testimony:

“I solemnly declare that I will speak the truth, the whole truth and nothing but the truth.”

While they are testifying, witnesses may not discuss their testimony during courtroom breaks with anyone, including members of the prosecution or defence who called them.

The Trial Chamber may warn a witness of the duty to tell the truth and the possible consequences of not doing so. If a chamber has strong grounds for believing that a witness has knowingly and wilfully lied, it may initiate proceedings against him or her. If found guilty for giving false testimony, the witness faces a maximum penalty of 100.000 Euros, or seven years in prison, or both.