Introduction
An expert witness is a person called upon to testify in court, that has the requisite knowledge or experience, skills and, or education to provide a scientific, technical, or other specialized opinion about the evidence or any disputed issue in the course of litigation. Contemporary criminal trials across the world have shown great interest in the role played by expert witnesses and their evidence tendered in court. Experts normally give opinions which the judge(s) may or may not admit, depending on the weight and admissibility criteria of such evidence when tendered in court. International criminal tribunals likewise have utilized the efforts of expert witnesses and their evidence tendered has helped to clarify many technical issues that seek such expertise knowledge. In one case before the International Criminal Tribunal for the Former Yugoslavia, 13 expert evidences were used on different issues.
This article discusses the role expert witnesses have played generally in criminal trials and in particular during the AFRC Trials at the SCSL. The article brings out the nature of expert evidence, the criteria for tendering such evidence, what is admissible and how such evidence may influence the decisions of the judges in the Trial Chamber.
Expert witnesses are called upon by either the prosecution or defence to provide materials and information that is outside the ordinary experience and knowledge of the court, thereby aiding the court on disputed issues, or to helping one of the parties to prove a particular case that is outside the common experience of the court. The scope of expert evidence covers a broad spectrum and touches on a variety of disciplines.
International criminal trials outline certain criteria as to how expert evidence can be admissible. Firstly, the subject matter should be beyond the ordinary experience of the court and it is required that the testimony should prove or disprove the issue in question. If the matter is within the knowledge and experience of the court then such evidence will not be admitted. Secondly, the expert evidence must be relevant in the sense of assisting the Trial Chamber in determining an issue in dispute. Irrelevant evidence that does not assist the Court will be rejected by the Trial Chamber.
Moreover, expert witnesses should have the necessary qualifications and methods required of formulating their theories. If from cross-examination or proven otherwise that the witness lacks the relevant qualifications, the evidence will not be described as “expert” and may be excluded. This is because expert evidence is opinion evidence, and opinion evidence of non-experts is not admissible in criminal trials because it constitutes hearsay. In other cases, the evidence will be admitted and the question of qualifications of the expert will be treated as to relevance and the weight of the evidence tendered. This may also be a proper basis for cross-examination by the opposing party.
Even though one party is calling the expert witness, the independence of the expert and the evidence to be tendered, is of paramount importance. In Akayesu (9th.March 1998), the Defence was not allowed to bring forward one accused as an expert witness to counter the evidence of a historian expert called by the Prosecution. The accused expert witness was rejected because the Trial Chamber could not be assured of the impartiality of the evidence he was to present in court.
Expert witnesses may be restricted from giving opinions relating to the “ultimate issue” of the case. Such expert evidence may not be admitted if it gives an opinion on the central issue which the court has to determine. International criminal trials do not lay emphasis on matters expressing the ultimate issue but whether such evidence will assist the court. Thus Zainab Bangura’s Report for Trial Chamber 2 was admissible because among other things it may assist the Trial Chamber in arriving at a decision on the gender-based crimes constituted in the charges of war crimes and crimes against humanity as supposed by the Prosecution.
Furthermore, the expert witness must not usurp the powers of the Trial Chamber as Lawton L. J. puts it in Turner (1975) “the fact that an expert witness has impressive scientific qualifications does not by the fact alone makes his opinion in matters of human nature or behaviour within the limits of normality any more helpful.” The court should make the factual findings on the evidence and the expert witness is to express an opinion on them. The expert is called upon to draw inferences and to formulate opinions from particular facts which are not obvious to the layman but which his professional knowledge and experience enables him to perceive. “An expert opinion could be relevant if the facts upon which it is based are true….It is for the Trial Chamber and not for the expert to determine whether the factual basis for an opinion is truthful.”
The Trial Chamber should always be in control of the trials as they are not bound to accept any evidence from experts because it is the Trial Chamber that makes the decisions about evidence proffered, which includes decisions as to the evidence to be accepted and rejected.
Expert Witness Evidence before the Special Court
Three members (Alex Tamba Brima, Brima Bazzy Kamara and Santigie Borbor Kanu) of the former AFRC were indicted and arraigned at the SCSL. The accused were charged with various crimes ranging from war crimes, crimes against humanity and other serious violations of International Humanitarian Law. The trials began on the 7th. March 2005, in Trial Chamber 2, before Justices Doherty (Presiding), Lussick and Sebutinde. Fifty-nine (59) witnesses testified for the Prosecution of which four (4) gave expert evidence, three of which were in open court sessions. Among other things Zainab Bangura testified on the concept of the “Bush Wife Phenomenon” during the war in Sierra Leone; Colonel Richard Iron gave evidence on the AFRC Command Structure and how effective was the command during the AFRC regime (both in Freetown and in the jungle after they were ousted). Lieutenant Colonel John Petrie testified as to the identity of the First and Third Accused of the AFRC Indictees. An Undisclosed Expert Witness gave evidence on the recruitment and use of Child Soldiers during the war in Sierra Leone but his evidence was not made public for security reasons.
Expert Testimony for the charge of Forced Marriage
During the AFRC Trials, the Prosecution called on Zainab Bangura to give evidence as an expert witness on ‘forced marriages’ during the war in Sierra Leone. She prepared a report referred to as the “Bush Wife Phenomenon”. The Trial Chamber certified her as an expert because she has professed knowledge on gender-related issues. According to the Report she described forced marriage within the Sierra Leone context as the physical abduction of a girl or woman by a rebel soldier during the war. When an attack was carried out the rebel/soldier would restrain the girl/ woman and proclaim her to be his “wife” (‘yu na mi wef’), this implies control and permanence of the relationship. Consent and the possibility to protest at such “marriage” is impossible as the girl/woman was already a hostage of the rebel/soldier. She stated that even though some of these ‘bush couples’ may have legitimized their relationship, the origin of these bush marriage relationships emanated from abduction during the war. The rebels/soldiers did not seek the consent from the girl or her family so this constituted “forced marriage” which should be a war crime in the Sierra Leone context. The Prosecution was trying to prove that ‘forced marriage’ constituted war crimes and crimes against humanity as it affects the social and psychological status of the girl/woman victim. If upheld by the Trial Chamber then it will be an international precedent to convict persons of this type of wartime gender-based violence.
Initially the Prosecution went straight to the tendering of the Report during examination in chief. The Defence objected that it was premature to tender the document without cross examination as to her being an expert witness and the nature of her report. They also questioned the witness’s certification as an expert. The Report contains more personal experiences and perceptions than independent factual information or scientific data. It was alleged that she may not be independent as she has been agitating for women’s rights. The Defence also pointed out that the Report affects the “Ultimate Issue” in the case and should be considered hearsay.
The Prosecution responded, that the Defence was taking the Court backwards for the Trial Chamber had already certified the witness as an expert. It was argued that claiming her Report to contain hearsay or personal assessment was a matter of evidentiary weight and did not go to admissibility. The Prosecution pointed out that in any event hearsay evidence is admissible in the SCSL, but the opposing party has the option to cross examine the witness as to the veracity and reliability of the hearsay statement. The Trial Chamber stated that the Report should only be tendered after cross examination of the expert witness. After cross examination, the same issues were raised by the Defence and after the Prosecution responded. The Trial Chamber finally accepted the Report into evidence.
Expert Testimony as to Command Structure
Colonel Richard Iron had first testified in the CDF Case and therefore when he testified on the AFRC case, his certification as an expert was not contested by the Defence. In the AFRC Trials, he explained about the command structure and function of military operations during the AFRC regime. He pointed out the difference between span and chain of command in a general army structure before he related it to that of the AFRC. He showed how military operations are broken down into staff and branches. According to him, the staff/branches in a traditional army structure, ranged from G-1 to G-5. His research methodology focused on whether the AFRC had a military hierarchy and structure; whether it exhibited the characteristics of a military organization; whether its strategic aims and objectives were transferred to tactical activity on the ground; and whether its command was effective.
Colonel Iron commented that he was surprised to find that there was no G-2 and G-5 within the AFRC rank and file but there existed other positions that were within the AFRC which are not in regular armies. For instance, the AFRC placed the Camp Commander in the position of the G-4. This does not mean that the group was not operating as a military organization. He said that the AFRC Command was a highly effective military force because it exhibited characteristics of traditional military organization that encompasses command, planning, orders, recruitment and training, lessons learnt and procurement. The Prosecution led the expert witness to determine the extent to which the AFRC was functioning as a military organization in the sense that it was effective. He did not focus on the individual responsibility of the AFRC accused but on the command structure as an organization.
The Defence again submitted an objection as to the admissibility of the evidence in relation to the ‘ultimate issue’ suggesting that effective command is an issue that will prejudice the trials. They also challenged Colonel Iron’s limited exposure to sources in formulating his report as he failed to interview most of the leaders of the AFRC. They claimed that Colonel Iron had restricted himself to what the Prosecution had already covered, thereby compromising his independence. The Trial Chamber considered the report to be relevant and therefore admissible, but will take the Defence arguments into consideration when considering the weight to give his evidence.
Further Expert Evidence
Lieutenant Colonel John Petrie gave testimony on the identification of the First and Third Accused, Alex T. Brima and Santigie B. Kanu, in the AFRC Trials. The SLCMP does not see this witness as giving expert testimony but identification evidence.
Witness TF1-296 gave evidence as an alleged expert on child soldiers in closed sessions testimony.
Conclusion
The procedural rules in International criminal trials allow the judges to exercise their discretion to either admit or reject expert opinions very widely, and even when they fall short of the necessary criteria for admissibility. However such expert evidence may influence the decision of the judges during the administration of justice. The SLCMP is mindful of the fact that expert opinion should be given serious consideration before decisions are taken on them as no two opinions are the same and can only be applied mutatis mutandis.