It has been argued that there are issues which simply cannot be
decided without expert guidance. Expert opinion evidence is
therefore readily received on issues relating to, inter alia,
ballistics, engineering, chemistry, medicine, accounting and
psychiatry. The question that, however, poses itself is whether
expert evidence is in all circumstances necessary.
Phipson (Evidence, 11th edition) and Hoffmann
(Evidence, 2nd edition) both point out the dangers
inherent in expert testimony. The inability of the court to verify
the expert's conclusions and the tendency of experts to be
partisan and over-ready to find and multiply confirmation of their
theories from harmless facts are problems that can easily occur
when accepting expert evidence.
There has been some reluctance to convict an accused solely on the
uncorroborated evidence of an expert, but there is no rule that a
court cannot make a finding solely on the evidence of an expert. In
saying this there are still certain kinds of expert evidence that
are treated with more circumspection than others and in the cases
of Kunz v Swart 1924 AD 618, Annama v Chetty 1946 AD
142 and recently the case of Levin v Levin 2011 SCA
114 handwriting evidence was treated with caution.
In the case of Levin v Levin (supra) the Supreme Court of
Appeal dismissed an appeal against the decision of the South
Gauteng High Court which found a will to be valid. Briefly the
facts of the case were as follows:
On 3 March 1999 and 8 August 2001 (the 2001 will) respectively, the
deceased executed two wills which were in a series of at least
nineteen such documents said to have been made by her. The one
dated 3 March 1999 dealt with the deceased's assets in Israel
which the deceased bequeathed to, the first respondent, being one
of her daughters (X) and X's children (the appellants). The
2001 will, related to her assets situated in South Africa and the
deceased nominated X as executor (together with her accountant and
the Standard Bank of South Africa Ltd) of her estate and granted X
and the appellants further, substantial bequests. Under the
disputed will, which was dated 4 August 2002, on the other hand, in
addition to appointing a new executor, the deceased bequeathed her
estate as follows – (a) 25 per cent to each of her
children, (b) R50 000 to her doctor and (c) the remainder of her
estate to be shared equally among her grandchildren. The purpose of
this new will was to restore peace to her family as they would all
share equally in the estate upon her death. The appellants brought
an action in the court a quo which was then taken on appeal on the
basis that the signature on the will was not that of the
deceased.
In order to determine the validity of the signature on the will the
appellants relied on a reputable hand writing expert to give expert
evidence. The expert examined the testatrix's signature on many
documents including cheques, letters and the previous wills. In the
first of two reports prepared by the expert on the authenticity of
the testatrix's signature in the disputed will, he expressed
the following view:
"If on 4 August 2002, the deceased's general health had
markedly improved – compared with the state of her
muscular control and eyesight, demonstrated in the signatures in
the will written some twelve months earlier, it is my view, that
she was, in all probability, the writer of the disputed signatures.
If, however, it can be proved that her eyesight and muscular
control had dramatically deteriorated during the intervening period
between the penultimate and the questioned will, then there is in
my view, a strong possibility that the disputed signatures are very
good freehand, simulated forgeries."
What the expert had not been told (after being furnished with
further signatures of the deceased), was that the deceased had in
fact undergone an eye cataract operation after signing the 2001
will. According to one Dr Deist, corroborated by X, this procedure
had significantly improved the deceased's vision and hand-eye
coordination. Dr Deist opined that it was reasonable in the light
of this improvement to expect the deceased's handwriting to be
neater. The expert then conceded that in addition to this operation
he was not aware that the deceased was blind in one eye and did not
consider the deceased's position when she signed the documents
and that all these factors were relevant to his enquiry. While he
still nursed some misgivings about the genuineness of the signature
in the disputed will, he fairly conceded that he would yield to
direct evidence to the effect that the signature was that of the
deceased.
The court embarked on one simple enquiry to solve the debate
surrounding the signature. Upholding the decisions in Kunz v
Swart and Annama v Chetty (supra) the court held that where a
judge has arrived at a decision based on the surrounding facts and
based on the evidence from direct witnesses, then the evidence from
an expert which is in conflict with these two aspects can be
disregarded.
It is safe to say that a judge in a civil or criminal trial cannot
play the role of an expert. The parties to an action will call an
expert whose function in a trial it is to assist the court to reach
a conclusion on matters on which the court itself does not have the
necessary knowledge to decide. It is not the mere opinion of the
witness which is decisive but his ability to satisfy the court
that, because of his special skill, training or experience, the
reasons for the opinion which he expresses are acceptable. It is
therefore for the court ultimately to decide whether an
expert's opinion is to be relied on or not and to determine
what weight (if any) has to be given to it.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.