If an adjudicator fails to address an issue, for instance a key defence issue, is that a breach of natural justice, and potentially fatal to enforcement of the decision? In RGB P&C Ltd v Victory House General Partner Ltd the court said that, where the adjudicator has deliberately, but wrongly, declined to address an issue, particularly a crucial defence, it may well be that the adjudicator has not decided the dispute referred to them. Where, however, they have not expressly taken such a deliberate decision, but appear not to have addressed every issue, the more likely conclusion is that the issue is subsumed within consideration of the dispute as a whole.
The judge noted that the case of Pilon v Breyer had left open the possibility that an inadvertent failure to consider one of a number of issues might render a decision in breach of natural justice, but it would not ordinarily do so and it was difficult to identify any case in which a decision had not been enforced for this reason. The rarity of such cases seemed to be for two reasons. An inadvertent failure to address a particular issue is in the nature of an error within the adjudicator’s jurisdiction rather than a breach of natural justice, but, if that was wrong, it would be an unusual case where the court would both infer that an issue had not been addressed and conclude that that failure was so significant that it meant that the adjudicator had not decided the dispute referred to them and/or that the conduct of the adjudication was so unfair that the decision should not enforced. The more significant the issue, the less likely it is to be inadvertently overlooked; the less significant it is, the more likely it is that it had been taken account of in the round.