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A dedicated prosecution division within the Office of the Prosecutor (OTP) is responsible for presenting cases in court, which is OTP’s other main responsibility besides investigations. The courtroom is, of course, the place where the guilt or innocence of each accused is ultimately established. Here the Prosecution strives to use the results of investigations to obtain convictions against the accused who are sitting in the dock.

The OTP prosecution division, which consists of trial and appellate sections, employs experienced trial attorneys from a range of countries, most of them with a long track-record in the prosecution of complex cases in their national jurisdictions.

Trials at the ICTY are heard before three independent judges. There are no juries in trials before the ICTY. The parties are principally responsible for the presentation of evidence before the court. The prosecution bears the burden of proof, and the defence may not even have to present any evidence if the judges rule that the prosecutors do not have a case against the accused.

At the end of the presentation of evidence, the Trial Chamber will deliver a judgement. If the accused person is convicted, the judges will also pass a sentence. Both parties have the right to appeal the judgement. The prosecution will often appeal a judgement not only if an accused is acquitted on some or all of the charges, but also if the sentence appears to them to be inadequate. The appeal process is held before the Tribunal’s Appeals Chamber.

Sometimes a trial is not required for a conviction. That is the case if the accused pleads guilty to the charges in the indictment. Usually guilty pleas only come about as a result of negotiated plea agreements between the prosecution and the defence.

The Prosecution Team

For each court case the OTP assigns a prosecution team which is responsible for representing the prosecution through the pre-trial and trial phases. The trial team consists of the team leader - a senior trial attorney, assisted by other trial attorneys, lawyers, a case manager and other support staff. Within the prosecution team the strategic and other legal decisions are made by the senior trial attorney in consultation with other members of the team. This will include the sequence in which the prosecution witnesses are called.

As team leader, the senior trial attorney will allocate work amongst the team members. The lawyers in the team are responsible for the taking of evidence in court, from both prosecution and defence witnesses, and the preparation and filing of written submissions such as motions and briefs. The case manager and other support staff also play a crucial part in the case during the pre-trial and trial phases in assisting the trial team in running the case in the most effective and efficient way.

In some large trials involving several accused, more than one senior trial attorney can be appointed to the prosecution team, while in some cases trials have also been lead by a prosecution team headed up by a trial attorney.

Pre-Trial Phase

The pre-trial phase is the period between the initial appearance of an accused before the court and the beginning of the trial. It is an important phase during which preparations are made for a fair and expeditious trial under the supervision of a designated pre-trial judge.

During this period, the prosecution team will prepare a pre-trial brief, a document which outlines the evidence which the prosecution plans to use during the trial to prove the commission of the crimes and the responsibility of the accused. A number of important legal filings will often be submitted during the pre-trial period, such as motions for judicial notice of facts of common knowledge or facts that were proven in other proceedings. This will help avoid repetition of evidence that has already been presented and accepted at previous trials.

The prosecution is also required to file a list of witnesses it intends to call at trial. Therefore important decisions have to be made by the prosecution team as to what is the most relevant evidence available, particularly as the judges will usually restrict the number of witnesses and time to be used at trial. The prosecution team will also have to consider whether the testimony of some witnesses could be submitted to the court in written form in accordance with Rule 92bis.

In the pre-trial phase the parties are required to communicate with each other on a number of issues. For instance, the prosecution has to fulfill its obligation to disclose any exculpatory evidence (evidence favourable to the defendant) in its possession to the defence. The prosecution will often engage in discussion with the defence with a view to seeking agreement on certain facts that are not contested. This allows the parties to focus on those issues at trial which are genuinely under dispute.

The Trial

Trial proceedings at the ICTY are held before a Trial Chamber which consists of three judges without a jury. The Trial Chambers form the first level of a two-tier court system, the Appeals Chamber being the second.

The task before the prosecution team is not an easy one. The fundamental principle of the presumption of innocence places a positive burden of proof on the prosecution and explains why a prosecution case will often feature many more witnesses and exhibits than the defence case. The question before the judges is not whether the prosecution is more convincing in its arguments than the defence. The question is, whether the prosecution manages to prove the guilt of the accused with so compelling evidence that the judges will have no reasonable doubt in the guilt of the accused.  

Every trial starts with an opening statement by the prosecution, in which the OTP’s senior trial attorney outlines the case against the accused. This usually lasts several hours. In most cases the defence chooses to give its opening statement later, after the presentation of the prosecution evidence.

During the main trial, OTP’s trial attorneys call witnesses and examine them in the courtroom with the goal of demonstrating the defendant’s guilt beyond reasonable doubt to the judges. The success of any trial depends greatly on the willingness of witnesses to come to the Tribunal to testify. There are several categories of witnesses:

  • Victim or Survivor witnesses: The majority of witnesses called by the prosecution are people who survived crimes, who witnessed them, or whose family members were victims of crimes. For these people, the act of testifying is an extremely courageous one as many of them still suffer physical and psychological trauma from the horror that they lived through. For this reason it is also important that the trial attorney who questions them in the courtroom gains their trust and treats them in a manner that will help them testify with confidence and clarity.
    >>Read some victims' stories and testimonies
  • “Insider” witnesses: Many of the Tribunal’s accused are high-level political, military or police leaders who are accused of 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 establishing the degree of responsibility of the accused.
  • Expert Witnesses: These witnesses are professionals who provide their expert opinion, under oath, on topics such as military doctrine, political structures, national laws in the former Yugoslavia, 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.
  • International witnesses: Diplomats or foreign military officers who were active in the conflict area at the time are sometimes called to testify for the Prosecution, especially if they held meetings with the suspects or other high-ranking civilian or military officials. They may, for instance, be able to provide proof that the suspect was informed about certain atrocities or military operations.
  • 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. Such testimonies may be crucial particularly in case of crimes such as mass murders where there were no survivors.

Most witnesses testify in open court without any protective measures, but the ICTY Rules of Procedure and Evidence also contain provisions for the protection of witnesses because of the sensitive and possibly dangerous situations they find themselves in due to their testimony.

The evidence will normally be given live in court by the witnesses, but the Rules also make provision for testimony by video-link and for the admission of written statements. In recent years, the prosecution has made growing use of that possibility, in response to demands to shorten trial proceedings. The witnesses may, however, be cross-examined in the courtroom by the defence.

Documentary evidence plays an important part in most trials before the ICTY, particular in cases involving high-ranking accused. Exhibits such as military orders, police reports, photographs and videotapes are often entered into evidence during the trial and discussed with the relevant witnesses.

With trial sessions scheduled often on four or five days a week, the trial attorneys’ work tempo is extremely demanding, as it is essential that they prepare thoroughly for the examination of each witness. Usually the trial attorneys meet with each witness before his or her court appearance in order to go through the contents of the testimony so that both the witness and the prosecutor know more or less what to expect in the courtroom. This practice of so-called “witness proofing”, which is allowed in some national jurisdictions and prohibited in others, has always been accepted at the ICTY, and it can enhance the fairness and the expeditiousness of the trial. It is particularly justified for the reason that witnesses usually testify about events which took place many years ago and reviewing the contents of their testimony beforehand can clarify their memory.

After the close of the prosecution case, if the judges assess there is no evidence capable of supporting a conviction, they can hand down a judgment of acquittal without need for further evidence or to hear the defence case. If the judges rule that the defendant does have a case to answer, the trial will proceed with the defence case. The defendant is not required to present any evidence, but the defence teams invariably do call witnesses to testify. The accused can also testify under oath in his own case.

The prosecution team does not rest during the defence case – the trial attorneys will engage in cross-examination of the defence witnesses in an attempt to discredit them or to cast doubt on their statements. Sometimes the cross-examination of defence witnesses may even present an opportunity to extract information that goes to prove the guilt of the accused. During the defence case the prosecution team may also prepare so-called rebuttal evidence, which is additional evidence that will be presented in response to issues arising from the defence evidence.

At the end of the presentation of the evidence, the judgment is delivered, and, in case of a conviction, an appropriate sentence is imposed.

Appeal Process

Both parties are allowed to appeal judgements as well as other decisions to the Appeals Chamber, the second level of the Tribunal’s two-tier court system. The Prosecutor will often appeal a judgement not only if an accused is acquitted on some or all of the charges, but also if the sentence appears to be clearly inadequate.

In the appellate proceedings the OTP is represented by specialised lawyers from the appeals section of the prosecution division. In other words, the arguments on appeal are not presented by the same attorneys who were on the trial team. There are good reasons for this, as the appeal proceedings are quite different in nature compared to the main trial. The appeal process is mainly conducted through written submissions, and the focus is heavily on whether the Trial Chamber applied the correct legal standards and whether it made any unreasonable findings of fact.

The OTP’s appeals team will also prepare responses to any appeals filed by the defence.

The appeal process is not a new trial. The Chamber will not re-examine witnesses that testified at trial. In some instances, however, where new evidence has come to light after the trial, the Appeals Chamber may allow additional witnesses to be called or new documents to be submitted.

At the end of the appeal proceedings, the Appeals Chamber will issue a written judgement, which is final. The appeals judgement will rectify any legal or factual errors that were found in the Trial Chamber judgment. The Appeals Chamber may also dismiss all grounds of appeal and confirm the first-instance judgement.

> Key Procedural Stages at the ICTY