Expert Witness
one who belongs to the profession or calling to which the subject
matter of the inquiry relates to and who possesses special
knowledge on questions on which he proposes to express an opinion.

There is no definite standard of determining the degree of skill
or knowledge that a witness must possess in order to testify as
an expert.

It is sufficient that the following factors are
1. Training and education
2. Particular, first hand familiarity with the facts of the case
3. Presentation of authorities or standards upon which his opinion
   is based.

An expert witness may base his opinion either on the first-hand
knowledge of the facts or on the basis of hypothetical questions
where the facts are presented to him and on the assumption that
they are true, formulates his opinion on the hypothesis.

Expert evidence is admissible only if:
1. the matter to be testified requires expertise and
2. The witness has been qualified as an expert.

How to present an expert witness
1. Introduce and qualify the witness;
2. Let him give his factual testimony, if he has knowledge of the
3. Begin the hypothetical question by asking him to assume certain
   facts as true
4. Conclude the question, by first asking the expert if he has an
   opinion on a certain point assuming that these facts are true
   and secondly, asking him, after he has answered affirmatively,
   to give his opinion on the point
5. After he has stated his opinion, ask him to give his reasons.

Hypothetical questions may be asked on an expert to elicit his
opinion. Courts, however, are NOT necessarily bound by the expert’s

What is the nature of expert opinions?
Suggested Answer:
Expert opinions are not ordinarily conclusive in the sense that
they must be accepted as true on the subject of their testimony,
but are generally regarded as purely advisory; the courts may place
whatever weight they choose upon such testimony and may reject it,
if they find that it is inconsistent with the facts in the case
or otherwise unreasonable.(Punzalan v. Commission on Elections,
et al., G.R. No. 126669; Meneses v. Commission on Elections, et al.,
G.R. No. 127900; Punzalan v. Commission on Elections et al.,
G.R. No. 12880; and Punzalan v. Commission on Elections, G.R. No.
132435 prom. April 27, 1998 citing Francisco on Evidence, Vol.
VII, Part 1, p. 662)

Testimony of handwriting expert not indispensable to COMELEC.
Handwriting experts, while probably useful, are not indispensable
in examining or comparing handwriting; this can be done by the
COMELEC itself. It was ruled by the Supreme Court that evidence
aliunde is not allowed to prove that a ballot is marked, an
inspection of the ballot itself being sufficient.