Case: Minister for Immigration and Ethnic Affairs v Wu Shan Liang [1996] HCA 6 ; (1996) 185 CLR 259
Outcome: applied
The second basis for concluding that this purported Ground is without substance is that it is no part of the function of the Federal Magistrates Court when reviewing a decision of the Tribunal, or for this Court on appeal, to question the " weight " given by the Tribunal to particular facts or considerations. That is a matter for the Tribunal alone. In an oft-cited passage in Minister for Aboriginal Affairs v Peko-Wallsend Ltd [1986] HCA 40 ; (1986) 162 CLR 24 Mason J observed: ... The limited role of a court reviewing the exercise of an administrative discretion must constantly be borne in mind. It is not the function of the court to substitute its own decision for that of the administrator by exercising a discretion which the legislature has vested in the administrator. Its role is to set limits on the exercise of that discretion, and a decision made within those boundaries cannot be impugned... It follows that, in the absence of any statutory indication of the weight to be given to various considerations, it is generally for the decision-maker and not the court to determine the appropriate weight to be given to the matters which are required to be taken into account in exercising the statutory power... I say "generally" because both principle and authority indicate that in some circumstances a court may set aside an administrative decision which has failed to give adequate weight to a relevant factor of great importance, or has given excessive weight to a relevant factor of no great importance. The preferred ground on which this is done, however, is not the failure to take into account relevant considerations or the taking into account of irrelevant considerations, but that the decision is "manifestly unreasonable". ... See also: Minister for Immigration and Ethnic Affairs v Wu Shan Liang [1996] HCA 6 ; (1996) 185 CLR 259 at 281 2. It is also to be recalled that a principal reason provided by the Tribunal in the rejection of the claims being made was its conclusion that the now Appellant was not " credible " and was " not a reliable witness ". Such findings, it has been said, are findings " par excellence " entrusted to the decision-maker: Re Minister for Immigration and Multicultural Affairs; Ex parte Durairajasingham [2000] HCA 1 , 168 ALR 407. McHugh J there rejected an argument that a failure to provide reasons for a finding that a claim was " utterly implausible " constituted a breach of s 430 and, in doing so, observed: [67] ... However, this was essentially a finding as to whether the prosecutor should be believed in his claim -- a finding on credibility which is the function of the primary decision-maker par excellence. If the primary decision-maker has stated that he or she does not believe a particular witness, no detailed reasons need to be given as to why that particular witness was not believed. The tribunal must give the reasons for its decision, not the sub-set of reasons why it accepted or rejected individual pieces of evidence. In any event, the reason for the disbelief is apparent in this case from the use of the word "implausible". The disbelief arose from the tribunal's view that it was inherently unlikely that the events had occurred as alleged. No greater reasons need have been provided by the Tribunal in the present proceeding for its conclusions; nor need the Tribunal have explained what " weight " it gave to the November 2007 response.