(3) It is a defence to the publication of defamatory matter if the defendant
proves that--
(a) the matter was an expression of opinion of a person (the
"commentator" ), other than the defendant or an employee or agent of the
defendant, rather than a statement of fact, and
(b) the opinion related to a
matter of public interest, and
(4) A defence established under this section is defeated if, and only if, the
plaintiff proves that--
(a) in the case of a defence under subsection (1)--the
opinion was not honestly held by the defendant at the time the defamatory
matter was published, or
(b) in the case of a defence under subsection
(2)--the defendant did not believe that the opinion was honestly held by the
employee or agent at the time the defamatory matter was published, or
(c) in
the case of a defence under subsection (3)--the defendant had reasonable
grounds to believe that the opinion was not honestly held by the commentator
at the time the defamatory matter was published.
(5) For the purposes of this
section, an opinion is
"based on proper material" if--
(a) the material on which it is based is--
(i)
set out in specific or general terms in the published matter, or
(ii)
notorious, or
(iii) accessible from a reference, link or other access point
included in the matter (for example, a hyperlink on a webpage), or
(iv)
otherwise apparent from the context in which the matter is published, and
(b)
the material--
(i) is substantially true, or
(ii) was published on an
occasion of absolute or qualified privilege (whether under this Act or at
general law), or
(iii) was published on an occasion that attracted the
protection of a defence under this section or section 28 or 29.
(6) An
opinion does not cease to be based on proper material only because some of the
material on which it is based is not proper material if the opinion might
reasonably be based on such of the material as is proper material.