"It is well settled that absolute privilege attaches to all statements made in the course of judicial proceedings, whether made by parties, witnesses, legal representatives, members of the jury or by the judge. It extends to oral statements and to statements in originating process, in pleadings or in other documents produced in evidence or filed in the proceedings. It is said that it extends to any document published on an 'occasion properly incidental [to judicial proceedings], and necessary for [them]'.
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It is sometimes said that absolute privilege is founded on public policy considerations. It may be that, so far as concerns communications between officers of State in the course of their official duties, absolute privilege attaches by reason of broad considerations of public policy and convenience. However, a more precise basis was identified for that aspect of the privilege in Gibbons v Duffell, it being said in that case that absolute privilege attaches because it is 'indispensable to the effective performance of ... official functions'.
Whatever the position with respect to communications between officers of States, absolute privilege attaches to statements made in the course of parliamentary and judicial proceedings for reasons of necessity. Thus, it has been said that absolute parliamentary privilege arises from 'inherent necessity'. And absolute privilege attaches to statements made in the course of judicial proceedings because it is an indispensable attribute of the judicial process. It is necessary that persons involved in judicial proceedings, whether judge, jury, parties, witnesses or legal representatives, be able to discharge their duties freely and without fear of civil action for anything said by them in the course of the proceedings. Were civil liability to attach or be capable of attaching, it would impede inquiry as to the truth and justice of the matter and jeopardise the 'safe administration of justice'.
It may be that the various categories of absolute privilege are all properly to be seen as grounded in necessity, and not on broader grounds of public policy. Whether or not that is so, the general rule is that the extension of absolute privilege is 'viewed with the most jealous suspicion, and resisted, unless its necessity is demonstrated'."