Legacy website of the International Criminal Tribunal for the former Yugoslavia

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Investigations play a crucial role at the ICTY, as they form the basis for all prosecutions and trials. There is no investigative judge at the Tribunal - the legal process is initiated by the Prosecutor on the basis of information received or obtained from any source, such as individuals, governments, international, inter-governmental or non-governmental organisations, or UN organs. Once the Prosecutor is satisfied that there are reasonable grounds to believe that crimes within the jurisdiction of the Tribunal have been committed, an investigation begins.

The investigations division within the Office of the Prosecutor (OTP) was responsible for collecting the evidence and information which was then used for issuing indictments against suspected perpetrators. The Prosecutor issued the last indictments at the end of 2004, and since then, investigations have been conducted only to support ongoing pre-trial or trial proceedings or to search for fugitives.

The Prosecutor has the power to summon and question suspects, victims and witnesses, collect evidence and conduct on-site investigations, which include the exhumation of mass graves. In doing so, the Prosecutor may seek the assistance of the state authorities concerned. Pursuant to UN Security Council resolutions and the Tribunal's Statute, States are under an obligation to cooperate with investigations and prosecutions. In practice, however, cooperation has not always been forthcoming.

If the Prosecutor believes there is sufficient evidence to prosecute, an indictment containing a concise statement of the alleged facts and the crime or crimes with which the accused is charged is drafted and submitted to a judge for confirmation, along with supporting evidentiary material. The judge can confirm or reject an indictment, accept certain charges and dismiss others, or request more supporting evidence from the prosecution. The last indictments of the ICTY were confirmed in the spring of 2005.

When an indictment is confirmed, the judge may, at the request of the Prosecutor, issue an arrest warrant or an order for the indictee's detention, surrender or transfer, and any orders required for the conduct of the trial. As the Tribunal does not have its own police force, it cannot apprehend suspects and is entirely dependent on the assistance of state authorities and international bodies in the arrest and transfer of the accused.

The Crimes

The OTP investigates four categories of crimes: Grave breaches of the Geneva Conventions of 1949, Violations of the Laws or Customs of War, Genocide and Crimes against Humanity.

>> Statute of the Tribunal

The crimes investigated by the OTP differ from ordinary crimes. They were often large-scale events that took place across wide areas. Some lasted many months and were highly organised. They involved some of the worst atrocities seen in Europe since the Second World War – mass killings, torture, deportation, persecutions, enslavement, plunder, wanton destruction of towns or villages and wilful damage to religious institutions.

Some of the worst crimes in the former Yugoslavia occurred in the areas of Srebrenica, Prijedor, Foča, Sarajevo and Mostar in Bosnia and Herzegovina, Vukovar in Croatia, and Kosovo.

Types of Criminal Responsibility

The OTP can charge defendants with two types of individual criminal responsibility. The first is for personally planning, instigating, ordering, committing or aiding and abetting in a crime. Such responsibility encompasses the doctrine of joint criminal enterprise, which has often been used to describe situations where several persons having a common purpose embark on criminal activity. Whoever contributes to the commission of crimes by the group of persons or some members of the group, in execution of a common criminal purpose, may be held criminally liable.

The second is for being in a position of authority and knowing or having reason to know that a subordinate or subordinates were about to commit or had committed such crimes but failed to prevent or punish them. This is known as superior responsibility.

The Prosecutor can not charge states, organisations or ethnic groups.

Sources of Evidence

The first stage in any investigation is discovering that a crime within the jurisdiction of the ICTY has taken place and how serious it appears to have been. To do this, the OTP examines initial evidence from various sources.

In the very first phase of OTP’s investigations, a primary source of information was the final report of the Commission of Experts, a fact-finding body that was established by the UN Security Council in October 1992 to examine whether grave breaches of international humanitarian law were being committed in the former Yugoslavia.

Witnesses were crucial in building the first cases. While the war was still going on, reaching crime scenes and witnesses in the region was difficult, even impossible. So investigations began in refugee centres scattered throughout the world, where hundreds of thousands of people had sought refuge from the conflicts. Their testimonies provided invaluable crime base evidence and links to the persons who had physically committed the crimes, such as soldiers, camp guards and wardens.

By working with victims, refugees and displaced persons, several humanitarian organisations and other institutions they were also able to gather first-hand accounts of events and other information, which was passed on to the OTP to examine.

As cooperation with the region improved, areas where crimes had been committed, including mass graves, and certain documentary evidence held in national archives became more accessible and contributed to the prosecution of more senior political and military leaders from all sides in the conflict.

Categories of Witnesses

The OTP deals with many different categories of witnesses during the investigation, including victims and survivors, experts, internationals and insiders.

Victim or survivor witnesses are a crucial source of evidence as they are in a position to describe what took place and identify those involved. This is critical in the preparation of the indictment and can often lead to new sources of evidence. Actually finding the first witness can sometimes be difficult. Investigations often started years after the events took place, and witnesses might have moved away or died. For example, in the investigation of the events around Čelebići, investigators tracked down the initial witness in Chicago.

The passage of time and the removal to a location far from where the events unfolded can dull the memory of some witnesses. Often, while the evidence given will show who was directly involved, those identified tend to be lower level suspects, and eyewitness evidence cannot identify where the orders came from or who the commanding officers were. Finally, a witness may decide not to testify because they wish to forget the events that took place, or they are psychologically unable to give evidence. They may also fear intimidation or reprisals.

Expert witnesses are connected to the investigation in some manner but were not directly involved in the events. It can include, for example, military and political analysts called to provide a background to what was taking place across the country or to interpret document collections, or scientific researchers who may have helped uncover evidence such as mass graves or examined crucial aspects of the evidence such as DNA samples.

International witnesses include diplomats or foreign military officers who were active in the conflict area at the time and can often provide valuable information to the OTP, 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.

Insider witnesses can provide valuable evidence in linking the accused to the crime base through direct or circumstantial evidence. Insider witnesses tend to be either witnesses with "blood on their hands", or those who have been privy to the orders given.

>> Read some victims' stories and testimonies

The Investigations Division

Until 2008, the OTP had its own investigations division tasked with collecting and examining evidence, identifying and questioning witnesses and conducting on-site investigations. While investigations now form part of the prosecutorial division it still employs around 50 investigators from across the world. Their training and experience in criminal investigation techniques in national systems have been merged into a unique international criminal prosecution system.

Given the specialist nature of the crimes, the OTP also has a Military Analyst Team, most of whose members have a military background, and a Leadership Research Team, with staff from varied academic and linguistic backgrounds and specialising in the former Yugoslavia. Their job is to analyse documentary, intercept and open source materials linking the persons most responsible for the crimes to the actual crimes themselves.

All trial related investigation matters are supervised by the Chief of Prosecutions.

When evidence pointed towards serious crimes within the ICTY mandate, the OTP would form a team to investigate these allegations further. While in most national systems, this investigative role falls on the police, at the ICTY a multi-disciplined investigation team is set up with members from within the OTP. It generally comprises investigators, lawyers and analysts or research officers. Interpreters also play a vital role, not only for written translations, but also because they will frequently have to interpret in delicate situations involving politically or militarily sensitive information or emotionally stressful testimony, such as that of victims of rape or torture.

This team undertakes further, more detailed investigation, which includes a review of the evidence thus far collated, the location and interviewing of witnesses, crime scene analysis, and forensic investigation and examination. The ICTY does not have its own police unit and therefore relies extensively on different state bodies to analyse forensic areas and report back.

For example, in the investigation of the events following the genocide in Srebrenica, the Netherlands Forensic Institute conducted textile analysis from blindfolds and DNA analysis, the United States Bureau of Alcohol, Tobacco and Firearms examined ballistic evidence, while a soil specialist from the United Kingdom compared soil samples. It was discovered that the mass graves had been disturbed and bodies had been removed in an effort to cover up the extent of the crime. Forensic analysis of secondary graves through the ballistics, DNA, textile and soil led to them being paired with primary graves and to the identification of some of the bodies.

The Investigation Strategy

When an investigation is assigned to a team, the team leader and legal advisors formulate an investigation strategy and each team member is assigned set responsibilities. Evidence is collected during the entire process. A time frame for the investigation is set and missions to the area where the alleged crimes took place are planned.

In the early years, investigations had to be conducted with limited resources and under dangerous conditions, as the war was still ongoing. The Tribunal's legitimacy was not recognised by certain authorities in the region, who denied investigators access to crime scenes and witnesses, in some cases even to investigate alleged crimes committed against people from their own state whom they were meant to represent.

As a result, the OTP decided to follow what has been called a pyramidal investigation strategy, starting from the bottom, in other words, with crime base evidence and lower-ranking persons who actually committed or ordered the crimes. Investigations began in refugee centres throughout the world, where victims and witnesses were able to provide evidence implicating the persons who had physically committed the crimes, such as, for example, the persons in the camps where they were detained or the camp commanders.

As the evidence grew, investigators began working up the pyramid to the persons who could be regarded as most responsible for the crimes.

During the "top down" investigation phase, the challenge was to link the crime base incidents with persons who did not physically commit the crime but who may have ordered, planned, implemented or facilitated key parts of any common scheme, strategy or plan. As in any organised crime or human rights abuse investigations, legally linking the persons higher up to the actual crimes committed is not easy and takes time. While the crime base evidence was being identified, many others within the OTP were engaged on compiling profiles of potential suspects and identifying and gathering documentary, intercept and insider evidence. This could not be achieved overnight and it took several years of work by many dedicated present and former members of the OTP.

Most of the investigative work is done in The Hague, where documents and other evidence is collected and analysed. Cases are selected on the basis of criteria set by the Prosecutor and prioritised in line with available resources.

Part of the investigation takes place in the field and usually starts with the interview of witnesses. After statements are obtained with the help of interpreters, investigators and scenes of crime officers go to the alleged crime scene, test the information received and look for corroboration. The scene of the crime is photographed, sketched and videotaped and combed for physical evidence, such as cartridge casings, bullet fragments and projectiles.

If there are indications that mass killings were involved, investigators seek the assistance of forensic teams. Once sufficient evidence is obtained to point to the existence of mass graves, the exhumation process commences.

During some investigations, the OTP was able to interview the suspects themselves. In such situations, the investigators would have to warn the person in question that he has the right to remain silent, that any statement he makes may be used in evidence, and that he has a right to an attorney. If a suspect is not properly cautioned it could lead to the invalidity of evidence taken in interviews. Some accused persons agreed to provide information to the OTP after they were transferred to the custody of the Tribunal.

The Indictment

Once the Prosecutor is satisfied there is sufficient evidence to substantiate an dindictment being issued, an indictment is drafted identifying the suspect and listing the charges against him or her. A single indictment can identify multiple accused in what is called a joinder of accused and almost all indictments contain more than one charge and deal with two or more crimes.

The OTP conducts an internal assessment as to whether the evidence collected will support the charges within the indictment and exactly how the actions of the accused fit in to the structure of the crimes within the jurisdiction of the ICTY.

It was general practice to tie as many accused to the indictment as possible in order to minimise the reiteration of facts and avoid multiplying the work of the Tribunal. The disadvantage to this approach was getting all the accused in the same place at the same time to try them all, and that was where state cooperation was critical, but often lacking.

When an indictment is prepared, the Prosecutor forwards it, together with the supporting material, to the Registrar. The Registrar consults with the President, who then refers the matter to the Bureau (composed of the President, Vice-President and the Presiding Judges of the Trial Chambers). When the Bureau determines that the indictment meets the required standard, the President refers the case to a designated Trial Chamber judge for review.

An indictment must be confirmed by a judge before any suspect can be accused or any arrest made. There are rules governing the confirmation procedure. The designated judge examines the evidence presented by the Prosecutor, which only has to support a prima facie case and does not have to reach the level of beyond a reasonable doubt, which is applied later in the trial.

The confirming judge has more options than simply confirming or rejecting an indictment. He or she can accept certain charges and dismiss others. More supporting material and evidence from the Prosecutor for a certain charge can be requested, or clarification on a point of law can be asked. The confirming judge cannot suggest additions, but can recommend a dropping of charges if he or she thinks there is no reasonable chance of conviction.

Upon confirmation of an indictment, the judge can, at the request of the Prosecutor, issue a warrant or order for the arrest, detention, surrender or transfer of the indictee.

An indictment is not set in stone. Due to the complexity of the cases before the ICTY, in many cases the investigations were still ongoing when the accused was brought to the Tribunal’s custody. Some indictments changed profoundly as new evidence came to light and events unfolded, particularly those concerning accused indicted a long time ago. Ratko Mladić, for example, was first indicted on 24 July 1995, and indicted a second time in November 1995, the second indictment detailing the charges brought against him for his participation in the events surrounding the capture of Srebrenica and the fate of thousands of Bosnian Muslim men arrested there by the Bosnian Serb forces. These separate indictments were merged into one in 2002.

Indictments may be sealed or made public. Indictments were sealed when the Tribunal determined that this was in the interest of justice. This decreased the risk of the accused fleeing or hiding before arrest. An example of a sealed indictment was the arrest by Austrian police and transfer to The Hague of the late general, Momir Talić, who travelled to Vienna to take part in a conference organised by the Organisation for Security and Cooperation in Europe (OSCE) in August 1999.

Although criticised for interrupting high-level members of government in their duties, sealed indictments can be necessary in the face of continuing non-cooperation. Louise Arbour, the Prosecutor between 1996 and 1999, defended the use of the sealed indictment by referring to 20 other outstanding arrest warrants that the Bosnian Serbs were making no effort to execute.

In the case of a sealed indictment, once the accused is arrested or has surrendered voluntarily, a judge will order the indictment be made public. By 2006 all indictments were made public and none remained under seal.

Surrender, Arrest and Transfer of the Accused

The last stage of the investigation is the actual apprehension of the accused and his transfer to The Hague. Since the ICTY was created by the Security Council under Chapter VII of the UN Charter, all states are obliged to act on all Tribunal orders, including those for the arrest and transfer of accused persons. Unfortunately, this cooperation has often been lacking.

While it is the obligation of states to locate and arrest indicted individuals, the OTP has also formed a “tracking team” which gathers information about the movements and whereabouts of fugitives. Such information is then provided to the local authorities or international forces who can act upon it, as the OTP does not have the jurisdiction or the equipment to arrest the fugitives on its own. The tracking team, which consists of information agents from various countries, has contributed to the arrest of several indictees. Providing national authorities with exact data on the fugitives’ location can circumvent the passiveness of many states in searching for them.

The apprehension itself can range from the accused surrendering voluntarily, to being seized by the police. In 2005, Ramush Haradinaj, the then Prime Minister of Kosovo, surrendered voluntarily upon an indictment against him being made public. He was transferred to The Hague without delay. By contrast the Croatian general, Ante Gotovina, had sworn never to turn himself in and managed to flee from justice for more than four years. He was arrested by Spanish police in the Canary Islands before being transferred to The Hague.

The accused has the right to be informed promptly and in a language he understands of the nature and the cause of the charge(s) against him. After transfer to the UN Detention Unit in The Hague, the accused is brought before a judge for the initial appearance to ensure that all the rights of the accused are being respected.

Not all suspects are ultimately tried in The Hague. Under rule 11bis, the ICTY can transfer an accused to be tried before a national court. The strategy of the OTP has been to build the crime base and then indict the top-ranking leaders; once this crime base was built, the ICTY began transferring lower-level accused back to the states of the region to face trial before the national courts.

>> Read more on transfer of cases

The ICTY operates with the greatest of respect for the Rule of Law and safeguards the rights of the accused in accordance with international human rights standards. The ICTY believes in the principle of the equality of arms, that is, that both defence and prosecution should have the same resources with which to "fight the battle" in the courtroom. The accused has the right to a defence counsel, paid for by the Tribunal if the accused cannot afford counsel. There are also options for an accused to obtain his own counsel at his own expense, or share the costs with the ICTY. This legal aid programme costs the Tribunal about 8% of its budget. The accused also has the right to self-representation.