Ordinarily a tribunal – whether
judicial, arbitral or adjudicatory – may obtain technical advice at need
through the appointment of experts. In
this way, the tribunal need not contain members who are personally familiar
with all aspects of the type of construction which is in dispute. Expert witnesses may assist the tribunal
properly to understand the technical matters they are asked to decide. Expert witnesses are distinct from witnesses
of fact in that they are allowed to provide evidence of opinion. This may
involve interpretation and reliance on hearsay.
Arbitrators and adjudicators have
taken expert advice outside the formal boundaries of the tribunal over which
they preside. This happened quite recently where an arbitrator, outside the
hearing, telephoned an expert for technical advice.