Defamation Act 2005

It is a defence to the publication of defamatory matter if the defendant proves that —

the matter was an expression of opinion of the defendant rather than a statement of fact;

the opinion related to a matter of public interest; and

the opinion is based on proper material.

It is a defence to the publication of defamatory matter if the defendant proves that —

the matter was an expression of opinion of an employee or agent of the defendant rather than a statement of fact;

the opinion related to a matter of public interest; and

the opinion is based on proper material.

It is a defence to the publication of defamatory matter if the defendant proves that —

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;

the opinion related to a matter of public interest; and

the opinion is based on proper material.

A defence established under this section is defeated if, and only if, the plaintiff proves that —

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;

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

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.

For the purposes of this section, an opinion is based on proper material if it is based on material that —

is substantially true;

was published on an occasion of absolute or qualified privilege (whether under this Act or at general law); or

was published on an occasion that attracted the protection of a defence under this section or section 28 or 29.

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.