Normally witnesses can only give evidence about facts. Since
opinions are not facts, opinion evidence would normally be excluded
on the alternative grounds either that it is irrelevant or that it
does not prove anything.
However, the opinions of an expert are admissible to assist
the Commissioners to come to a conclusion of fact on a technical
matter or a matter of art or science, for example the value of a
piece of land at a particular time. An expert is an individual who
is qualified by long study or experience to give an opinion on the
matter in issue.
