The development of the disclosure of evidence in criminal proceedings both on the national and international level in the 20th century is remarkable. We have seen that both on the national and international level, this development is characterized by a strong increase of disclosure obligations for both parties.
Whereas an accused in the United States was, until the middle of the 20th century, occasionally legally prevented from even receiving his own prior statement in a case where his life was at stake, we can now state that the rights of the accused on both sides of the Atlantic are much better protected than before – this does not mean that they are always sufficiently protected; which is shown by the considerable amount of jurisprudence of the ECtHR on the matter, oftentimes, though by far not always, involving the United Kingdom.  However, the human rights aspect is only one of at least three purposes of disclosure. The second one, enhanced trial management, which was given more and more importance over time, has resulted in wider disclosure obligations not only on the side of the prosecution but also of the defence, a fact which, in turn, may run counter to the interests and rights of the accused. Thirdly, it is held, the truth-finding function of the criminal trial, regardless of the criminal justice system, has become increasingly important, a factor which has also contributed to a widening of disclosure obligations of both parties. Both trial management and truth finding are closely related with an ever growing influence of the court in the disclosure proceedings.
On the international level, we can observe a similar development, especially as concerns the Ad Hoc Tribunals. It is interesting to note that particularly defence disclosure obligations at the Ad Hoc Tribunals were very limited at the beginning, and have significantly widened during the existence of the Tribunals. This gives us the impression that, even though some officials at the beginning of the work of the Tribunals held otherwise,  the drafters of the relevant provisions were particularly aware of the necessity to protect the rights of the accused, trying to lay out the regulatory framework, one the one hand, in an ‘ideal’ way to keep up with the fair trial rights of the accused. After all: we know of no national code of criminal procedure which would contain a general provision, solely laying down, in an abstract way, the procedural rights of an accused, in the way this is done in Articles 21/20 of the ICTY/ICTR Statutes, or Article 67 of the Rome Statute. Admittedly, this regulatory technique is probably necessary in the way that, as pointed out in the introduction, none of the international criminal courts and tribunals are technically bound by the relevant international human rights treaties. Nevertheless, it appears that the drafters of the respective rules at the beginning wanted to ‘do everything right’, and not commit the same mistakes concerning fairness as were, from a modern viewpoint, made in Nuremberg. On the other hand, if we look at the highly controversial discussions at the Rome Conference, and later in the Preparatory Committee for the Rules of Procedure and Evidence, we can conclude that oftentimes all which could be agreed on regarding criminal procedure without endless discussions were fair trial rights of the accused, as contained in the relevant human rights documents. At the Ad Hoc Tribunals, there was no time for in-depth discussions on the matter. And indeed, the fair trial rights of the accused must form the basis of any kind of international proceedings, in order to reach acceptance of the international community, which is the basis of positive general prevention. Furthermore, however, many of the early judges at the international criminal courts and tribunals were (and some are still) not experienced practitioners, but rather academics, politicians or diplomats. The judges, with a rudimentary set of rules, were soon ‘caught up with’ by the reality of criminal proceedings, which forced them to find pragmatic solutions – some of which had direct consequences on disclosure. One important development in this regard is quite directly related to truth-finding: the protection of confidential information, be it on the grounds of (national) security interests or witness protection. In many cases, relevant evidence can only be obtained on the assurance of confidentiality; this is even more true in an international than in a national setting. The protection of confidentiality interests obviously restricts the fair trial rights of the accused. At the same time, however, the chambers of the international, which is a development we have also observed in the national jurisdictions, have acquired a more active role in monitoring the non-disclosure processes; indeed, the Lubanga case shows that the international judges are not willing to accept secret evidence in a major scale – even though the first decision to halt the proceedings was based on fair trial rights of the accused, it is obvious that the Chamber was dismayed by the behaviour of the Prosecutor, keeping the evidence secret from the Chamber itself, so it could not fulfil its tasks properly. This development is certainly partially due to the growing influence of the Continental-European tradition in international criminal proceedings, in which the judges traditionally acquire a more active role. However, the fact that the stronger involvement of the respective chambers happens on the national level as well, shows that this phenomenon cannot be fully explained with the ‘mix’ of adversarial and inquisitorial elements which is inherent in international criminal proceedings, regardless of a possible ‘convergence’ of the systems. Instead, it appears that additionally to the judges increasingly take pragmatic approaches to criminal proceedings, having in mind the rights of the accused, however, balanced with considerations of judicial economy, and truth-finding, which some of the judges, as we have seen, regard as the foremost goal of the proceedings.
From a functional perspective, it appears that the judges take a more active part in this truth-finding process, by demanding the submission or communication of evidence which is to be presented in advance. At the Ad Hoc Tribunals, this started with Dokmanović and resulted in the Pre-Trial and Pre-Defence Conferences and the pre-trial briefs which must be submitted to the chambers before the trial. It is meant to facilitate a better preparation of the trial by the Chamber; however, the involvement of the Chamber with, admittedly, not the evidence itself, but lists of evidence, does naturally have an effect on the judges, professional as they may be. At the ICC, this is even more true. The Rules themselves provide that the Pre-Trial Chamber receives not only lists of evidence, but copies of the evidence disclosed between the parties. Even though the exact scope of the evidence which must be communicated to the Pre-Trial Chamber is in dispute between the Chambers, the fact that this principle is ‘officially’ laid down in the Rules is remarkable. As we have seen, this agreement was only possible based on the assumption of the drafters that the Pre-Trial Chamber does not decide over the guilt of the accused. However, the complete record of the Pre-Trial proceedings is communicated to the Trial Chamber; with the bulk of disclosure taking place before the confirmation hearing and not the trial, this is a remarkable level of involvement of the chamber. And not only that: while the Rules are intentionally silent on disclosure during the trial phase, the practice of some of the Pre-Trial Chambers to involve the registry in the disclosure process has led to a situation where ‘automatically’ at least a large part of the evidence ends up in the record of the proceedings; and this practice has at times simply continued during trial. This means that also the Trial Chambers get to see the evidence in advance – if they wish to, that is; it appears, of course, possible that some of the judges, as a matter of principle, refrain from inspecting the record.
It appears from what we have seen, that disclosure (in the material sense) takes place between those participants in the trial which are responsible for conducting the truth-finding procedure. In an adversarial procedure, where truth is found by a ‘dumb’ jury on evidence presented by two parties, the evidence will be disclosed between the parties. With parties strictly following the procedural rules, one would not even need a judge. In an inquisitorial proceeding, on the other hand, it is essential that the inquisitorial judge gets the evidence beforehand, so that he can sensibly conduct the truth-finding process, in which parties, apart from the accused, are not needed at all, if the judge does everything right. These ideal pictures, however, as we have seen, are not reality anywhere in the world – in fact, in such an ideal world disclosure would not be required at all: The protection of fair trial rights of the accused can, regardless of the system, only work within a system of checks and balances. This is why the described ideal systems are not functional in a system committed to the rule of law, and this is also why disclosure is essential. The ideal picture of the adversarial process is based on the assumption that both parties have ‘the same chance of winning’; this sportsmanship element is also the reason why we can speak of the ‘fairness’ of the proceedings at all. If this were true, we would need no disclosure (as was the general practice until less than 70 years ago). This assumption, is unreal, since the prosecution will at all times be in a stronger position to investigate the case than the defence. This structural disadvantage of the defence must be compensated by giving the defence (in principle) the same level of information (‘equality of arms’). In an adversarial trial, the prosecutor must thus provide the defence with the necessary information. The fulfilment of this obligation by the prosecutor, however, must be controlled by some authority. In practice, this is nowadays, both at the national as at the international level, done by the judicial body dealing with the matter. And this control mechanism can only work if, at least in a case of dispute between the parties, the court gets access to the matter in dispute: the evidence. In an inquisitorial trial, the situation is a little more straightforward. Here also, in an ideal world, no ‘disclosure’ will be needed, since the inquisitorial judge will have collected the evidence himself in a purely objective manner. For the obvious disadvantages of this system, it has been abolished in most parts of the world – either the investigating judge will not be the same as the one who decides, or the investigation and prosecution is done by a ‘neutral’ prosecutor. The judge, in any case, retains the prior access to the collection of evidence, to enable him to investigate the matter in court properly. The prosecution will play a double role: it additionally performs a controlling function over the court. The same holds true for the defence, who will be allowed to play, in certain limits, a more partisan role. Both of the latter participants, however, are also called upon to be part of the truth-finding process in controlling the court. For the fulfilment of these tasks, they must have knowledge of the evidence beforehand, which means disclosure in the material sense.
The system of disclosure is therefore dependent on the distribution of the procedural roles within the proceedings as a whole.