The Court may choose to quash a decision where it is of the opinion that the decision is unfair because of a failure to give reasons. However, as is the case with all other grounds for judicial review, in the absence of any exceptional public interest reasons, the court must refuse to quash a decision (or award any other remedy) if it appears to it to be highly likely that the outcome for the person affected by the decision would not have been substantially different if the decision-maker had not failed to give reasons.
At first glance it may appear unlikely that giving reasons (or failing to do so) could ever have an influence on the decision itself; reasons are given after a decision is made, so how could the giving of reasons ever influence the substance of the decision made? The answer is that in some circumstances the process of formulating reasons for its decision would cause the decision-maker to properly focus its mind on the task before it and to consider relevant considerations. In these circumstances, the process of formulating the reasons to be given could have an effect on the substance of the decision itself. If so, it would be open to the Court to quash the decision on the grounds that the decision-maker failed to give reasons for its decision.