A person responding to a defamatory attack must take reasonable steps to ascertain the extent of the original publication before publishing a response; failure to make any inquiry as to the recipients of the original attack, even where the attacker has been uncooperative, will defeat a defence of qualified privilege where the response is published to a substantially wider audience. The test for whether publication to persons without the requisite interest destroys the privilege is objective. An agent who signs a defamatory letter on behalf of a company is protected by the company's qualified privilege even if the agent was not personally defamed in the original attack.
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