Pacific Conservation Biology Pacific Conservation Biology Society
A journal dedicated to conservation and wildlife management in the Pacific region.

Just Accepted

This article has been peer reviewed and accepted for publication. It is in production and has not been edited, so may differ from the final published form.

The defamatory potential of ad hominem criticism: guidance for advocacy in public forums

Hugh Finn


Ad hominem criticism seeks to discredit an argument by attacking the qualities of the arguer, rather than the merits of the argument. Although there are compelling reasons to avoid ad hominem criticism, it may sometimes be appropriate as a means of responding to ‘expert’ arguments advanced in public forums. However, conservation biologists should evaluate the defamatory potential of any proposed ad hominem criticism and consider whether the criticism: (1) impugns a person’s reputation in a trade, profession or business; (2) has a factual grounding that is based on evidence that could be used in court; and (3) is better formulated as a statement of opinion than as a statement of fact. From a defamation perspective, the purpose and context for an ad hominem criticism is critical and conservation biologists should never make isolated and unsupported ad hominem remarks. Conservation biologists should also be aware that there are circumstances in which critiques of the methods, analyses, logical approaches, and conclusions of an expert could be said to be defamatory of that person, but that courts also recognise the importance of scientific debate. Conservation biologists should carefully consider the wording of any proposed ad hominem criticism, particularly in terms of the precise facts to be alleged and the particular evaluative words or phrases to be applied, and should also ensure that the criticism has a proper purpose, is well-supported, and clearly distinguishes between comments that express an opinion and those that state a fact.

PC17022  Accepted 05 December 2017

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