DW: After last week's trial, the International Criminal Tribunal for the former Yugoslavia (ICTY) came to an end. How do you assess Slobodan Praljak's suicide?

Wolfgang Petritsch: I really must say that I was very shocked by the offender's suicide. Something like that should not happen. This serious security slip-up is inexcusable. Aside from that, the court has demonstrated its relevance in coming to terms with war crimes in former Yugoslavia. An unbelievable amount of testimony and research documenting the tragedy in Yugoslavia has been put together in The Hague in the form of an archive that future generations can access. The reconciliation process, however, must take place in the region itself. People and politicians need to be proactive.

Read more: The Hague Tribunal — A death and the painful truth

What needs to be done on a national level now that the ICTY is over?

The focus is clearly on national jurisdiction. At the beginning of 2000, I myself was in charge of establishing the criminal court in Bosnia. In addition to combating corruption, it is tasked with the continuation of ongoing war crimes trials and with the initiation of new ones. This must begin now. I think it is very important for the states affected by this tragedy to take responsibility for their own actions. Moreover, civil society, which is very strong in Serbia in particular and has already achieved a great deal, must work together towards reconciliation. This must finally begin in the individual states and among the successor states.

Was the International Criminal Court the wrong approach? Should local courts have been set up right away to avoid accusations in an external judiciary? 

The temporary International Criminal Court was established because Bosnia-Herzegovina was completely destroyed and did not have any institutions that could deal with this difficult process. During my term as high representative for Bosnia-Herzegovina (1999-2002), building state institutions also included a functioning judiciary that was able to come to terms with the past. This has been achieved in part. But each nation and each ethnic group has certainly not managed to break out of its victim mentality in order to pave the way for awareness of the fact that one can be both perpetrator and victim at the same time. This awareness is being undermined in part by politicians, as we now see in Zagreb.

What must be done on an international level to promote the process of earnest reflection?

If there is a lesson to be learned from The Hague — especially in light of the recent tragedy that will unfortunately overshadow all the trials — it is probably the fact that all those who have been involved have allowed the process to take place. No matter what the type of involvement, as victims or perpetrators, we must decide on beginning soon.

Read more: A deadly exit and a glimmer of hope in The Hague 

Many leading politicians still insist on cultivating their national and ethnic narratives. Milorad Dodik, the president of Bosnia's Republika Srpska, even goes as far as questioning borders.

I am convinced that questioning the borders will only lead to more tragedy. I believe that the ethnoterritorial aspect does play in but cannot be a decisive factor in bringing peace to the region. Moreover, European integration makes it clear that we can only find common ground in a larger area, both economically and culturally. For Serbia in particular, it should be an absolute priority to work together on a united Europe. Only in a united Europe will Serbia be united. The unification of the multiethnic and multinational entity — and everything else Yugoslavia embodied — can no longer be restored, but can actually develop in a positive manner within a larger Europe. This vision of the future must become more firmly entrenched in people's minds and hearts.

Read more: ICTY Hague Tribunal ends prosecutions of Yugoslav war crimes but legacy lingers 

Should the European Union pay more attention to Bosnia and offer membership?

Bosnia is the weakest link in the chain of the Western Balkans. Brussels must make its political will to have this country in the European Union, despite its political problems, more clear than it has until now. This message is not getting through! Instead, it comes across as a bureaucratic process and does not show faith in the sustainability of the region. But this future only exists in Europe, in the European Union. And that is why we should encourage the people there who are willing to support this path. This is the only way it is possible to introduce new policies in Bosnia as well. This is an important task that the EU has neglected until now, as many young people in particular are leaving the country.