What is the test for breach of natural justice?

Beals v. Saldanha, 2003 SCC 72, involved an allegation of breach of natural justice in the context of the enforcement of a foreign judgment. The appellants, Ontario residents sued in Florida on a failed land transaction, had notice of the action but claimed denial of their opportunity to assess the extent of their financial jeopardy as the claim failed to specify the exact dollar amount of damages and types of damages. Speaking for the majority, Major J. explained the (minimal) scope of the rule of natural justice as this (at para. 65 ): …In Canada, natural justice has frequently been viewed to include, but is not limited to, the necessity that a defendant be given adequate notice of the claim made against him and that he be granted an opportunity to defend.”