Single witness evidence (Zimbabwe)
Approach of courts
Where there is only a single witness to the crime certain special evidential rules apply.
A single witness may or may not also be a "suspect witness". If the single witness is also a "suspect witness" then the court must apply the special rules pertaining to single "suspect witnesses". These rules relating to single "suspect witnesses" are dealt with later.
The entire State case against the accused may rest upon the evidence given by a single State witness. This may be because the State has been able to produce only one witness against the accused. Alternatively, the State may have called more than one witness but the only evidence on which the guilt of the accused is going to depend is that of one witness alone. This situation has been referred to as a "boxing ring" situation because the outcome of the "contest" hinges on which of the two contestants is believed, namely the State witness or the accused.
With crimes other than perjury and treason, the court may convict an accused to convict an accused on the basis of the uncorroborated evidence of a single competent and credible State witness: s 269 CPEA.
There is obviously a risk which attaches to convicting the accused on the basis of the uncorroborated testimony of a single witness. There is a scarcity of evidence in the case and the testimony of the witness is the sole proof of the accused's guilt. In this situation the danger arises of poor observation, faulty recollection, reconstruction of evidence after the event, bias and any other risk that the circumstances of the case suggest. Before the court relies on such evidence it must be satisfied that the quality of evidence must make up for the lack of quantity.
In Mokoena 1956 (3) SA 81 (A) at 85-86 it was laid down that the uncorroborated evidence of a single witness should only be relied upon if the evidence was clear and satisfactory in every material respect. Slight imperfections would not rule out reliance on that evidence but material imperfections would. The court stated that single witness evidence should not be relied upon where, for example, the witness had an interest adverse to the accused, has made a previous inconsistent statement, has given contradictory evidence or had no proper opportunity for observation. However, in the later case of Sauls & Ors 1981 (3) SA 172 (A) the Appellate Division stated that there was no rule of thumb to be applied when deciding upon the credibility of single witness testimony. The court must simply weigh his evidence and consider its merits and demerits. It must then decide whether it is satisfied that it is truthful, despite any shortcomings, defects or contradictions in that testimony. The approach adopted in the Sauls case was followed in the case of Nyabvure S-23-88. See also Worswick S-27-88, Mukonda HH-15-87, Nemachera S-89-86 and Corbett 1990(1) ZLR 205 (S).
Beck JA in his article in 1986 Vol 1 No 1 Prosecutors Bulletin at p 18 says that in assessing the quality of the single witness' evidence, to decide whether the accused should be convicted on the basis of this evidence, the court should be most attentive to the nature of the witness, looking at his apparent character, his intelligence, his capacity for observation, his powers of recall, his objectivity and things like that. The evidence should be carefully weighed against the objective probabilities of the case, and against all the other evidence which is at variance with it. The court must have rational grounds to conclude that the evidence of the single witness is reliable and trustworthy and is a safe basis for convicting the accused.
Thus although an accused can be convicted on the basis of the uncorroborated testimony of a single competent and credible State witness, the court must assess very carefully the credibility and reliability of such a witness to see whether it is safe to convict on the basis of his testimony alone.
The courts have pointed out that proper investigation of criminal cases will usually uncover corroborating evidence and that it is seldom necessary to rest the entire State case upon single uncorroborated testimony. The courts have exhorted police officers and prosecutors not to be content with the production of evidence from a single witness. However, where it appears to a court that there are other witnesses who may be called, it has the power to call these witnesses itself in appropriate cases.
In Musonza & Ors S-217-88 the Supreme Court stated that as a general rule it is undesirable to rely solely and entirely on the evidence of the complainant, particularly in assault cases and more particularly where there are counter allegations of provocation, self-defence or justification in one form or another. The complainant in such cases has a clear bias and a reason to place himself in a favourable light and the accused in an unfavourable light.
In Tamba S-81-91 the Court stated that in assault cases, where there are other witnesses to the incident in addition to the complainant, these witnesses should be called and the case against the accused should not be left to rest upon the testimony of the complainant alone. It is wrong to deal with such cases as if they were a "boxing match" between the complainant and the accused. These two protagonists should not, as it were, be thrown into the ring with the magistrate as referee who, at the end of the bout, having awarded points for demeanour and probability, would name the winner (who would usually be the complainant). It was even worse if the magistrate is, as often seemed to be the case, a biased referee who worked on the unspoken assumption that the police would not have charged the accused if he was not the guilty one. This approach, said the Supreme Court, was dangerous, especially in assault cases where almost invariably the parties give conflicting versions of what was the cause of the fight and often both versions are partially untrue or exaggerated. Without evidence from bystanders, it was almost impossible to determine which version of the facts was the true one.
In Zimbowora S-7-92 the appellant had been convicted of three counts of contravening the Labour Relations Act. The State case had rested entirely on the evidence of the complainant. On appeal, the Supreme Court said that although the trial court was entitled to convict the appellant on the single evidence of the complainant, it was necessary for such evidence to be clear and satisfactory in every material respect. As the complainant was a witness with an interest to serve, the trial court was not only required to approach her evidence with caution but should also have sought corroboration of her evidence. The conviction was set aside by the Supreme Court as the complainant's evidence was not satisfactory in all material respects and no evidence was led to corroborate her assertions.
In Nduna & Anor HB-48-03 it was held that where a conviction relies on the evidence of a single witness, discrepancies in the witness' s evidence are not necessarily fatal. The discrepancies must be of such magnitude and value that it goes to the root of the matter to such an extent that their presence would no doubt give a different complexion of the matter altogether. The fact that the single witness is himself guilty of some unlawful conduct does not make him an accomplice in the crime which is charged. Where the accused, who were policemen, arrested and robbed a person who was crossing the border illegally, that person was not an accomplice.
Approach of defence lawyer
As the court is permitted to convict an accused to convict an accused on the basis of the uncorroborated evidence of a single competent and credible State witness, the cross-examination of the single witness by the defence lawyer must be aimed at establishing that the witness is not credible and reliable. If there are major or material aspects of the testimony of that witness are unsatisfactory, this must be indicated in the defence address. Defence counsel should then submit that in the light of these unsatisfactory features, it would not be proper to convict the accused on the basis of the witness's testimony. It is not enough simply to point to a few very minor defects or slight imperfections in the testimony, such as minor contradictions; despite these imperfections the court may still decide that overall the witness was a credible witness whose testimony is to be believed.
Where the testimony of the single witness was not corroborated by any other testimony, this point should be brought to the attention of the court, especially in assault cases involving so-called "boxing ring" type situations. The dangers of conviction on the basis solely of the uncorroborated testimony of the single witness should be emphasised.