Mahon v Air New Zealand Ltd [1984] AC 808   

Facts: Senior Justice Mahon oversaw the Royal Commission into the deaths of the New Zealand citizen's who died in an Air New Zealand flight. Mahon found there had been incompetent airline procedures and also that false evidence was given by officials of ANZ which was based on a predetermined plan of deception of the Royal Commission to conceal the airlines mistakes. Declared the evidence as lies and ordered ANZ to pay $150,000 to the cost of the Royal Commission. Mahon appealed to the Privy Council after the CA found that the order for costs was procedurally unfair.

The person making a finding in the exercise of such a jurisdiction must base his decision upon evidence that has some probative value. …The decision to make the finding must be based upon some material that tends logically to show the existence of facts consistent with the finding and that the reasoning supportive of the finding, if it be disclosed, is not logically self-contradictory (Lord Diplock at 820-821)

Held:
-   If you are to base your decision on adverse material, that adverse material has to be tested. In Mahon's conduct, he had not articulated that he was minded to reject the evidence he was hearing on the basis that they were lying.
-   He should have said "I think you were lying" and allowed a response.
-   Must listen fairly to relevant evidence that conflicts with the finding, that is, the affected person must not be ‘left in the dark’ about the risk of the finding being made and deprived of the opportunity to adduce additional material of probative value.
-   In this case it was a breach of procedural fairness that there was no probative evidence of a plan of deception through destruction of documents. Appeal dismissed
 Minister for Immigration and Ethnic Affairs v Pochi (1980) 31 ALR 666 

Facts: An appeal from a decision of the AAT under the AAT Act.  Plaintiff recommends the revocation of decision of Minister that the defendant be deported. The question for determination that was before the Tribunal was whether on the material before the Tribunal, the decision which the administrative decision maker made was the correct or preferable one. 
Principle: It is a well established principle that findings of material fact must ordinarily be based on logically probative material and that the decision of the tribunal, where relevant questions of fact are in issue, must be based on the facts and not on mere suspicion or speculation. (Deane J at 689)

Held:
-   Deane J: When an alien is liable to be deported the general rule must be that the conduct relied upon to show that the deportation order is in the best interest of Australia must be proved not merely suspected.
-   The tribunal and the Minister are equally free to disregard formal rules of evidence, but this assurance of flexible procedure can not go so far as to justify orders without basis in evidence having rational, probative force.
-   There is nothing to suggest that it was legislative intent (in the AAT Act 1975) that the tribunal should be free either of the requirement that its decision must be based upon findings of material fact or the requirement that such findings of material fact be based on logically probative material.
-   Attack on tribunal failed – it has not been shown that the tribunals decision was affected by error of law.
But see:
Australian Broadcasting Tribunal v Bond (1990) 170 CLR 321  

-   Courts are not there to adjudicate on findings of fact because finding of fact (including an inference drawn from primary facts) are no more than a step along the way to ultimate determination – however the determination which may be made based on the finding of fact vitiated by error of law ss5(1)(f) and ss6(1)(h) or made without evidence ss5(1)(h) and ss6(1)(h) may be reviewable.

Mason CJ:
i) Was there a reviewable decision?
- In general findings of fact aren’t reviewable independently of the ultimate decision.
 - Can only examine conduct on procedural grounds.
ii) Grounds of review
- The making of findings and drawing inferences in the absence of evidence is an error of law (i.e. findings are unreasonable). There is no error of law in simply making an incorrect/illogical finding of fact.
- Error of law under the ADJR act is intended to bear the same meaning as at common law. I.e. cannot review findings of fact, except where there has been an error of law.
- “ a finding of fact will then be reviewable on the ground that there is no probative evidence to support it and an inference will be reviewable on the ground that it was not reasonably open on the facts, which amounts to the same thing.”
- No errors of law were made in the course of findings of facts.
Deane J:
-   Procedural fairness requirements mean decision makers must not make arbitrary decisions; findings of fact must be supported by probative or logical evidence.
-   The requirements of procedural fairness can vary depending on the statute supporting them.
-   In general, procedural fairness requires decision maker’s to act rationally, reasonably, not arbitrarily, material/relevant considerations be included and immaterial considerations be ignored, decisions of fact must be supported by probative material. If this is not observed, it will be an error of law.

8. THE RULE AGAINST BIAS

Single test for bias in public decision making:
-   Might a reasonable observer apprehend that the decision maker might not resolve the matter with a fair and unprejudiced mind: Angliss; Liversey; Stollery; Polities; Laws; Ebner 
-   Actual bias does not have to be proved.  Ebner’s case establishes that there is no separate, free standing rule of automatic disqualification for direct pecuniary or proprietary interest. 
-   Is a “possibility” test rather than probability
-   The same “possibility” test applies to courts and administrators
-   The test accommodates the wide variety of situations in which it must be applied through attribution of knowledge to the reasonable observer: see eg. Re RRT; ex p H  Understanding of nature of proceedings, issues and conduct of decision maker
-   In some jurisdictions, an exception has been made for ‘domestic tribunals’. 
-   Because of the flexibility of the rule against bias, types of disqualifying bias cannot be categorised.  Some examples follow.  Remember however that the overarching question is whether the reasonable observer might perceive bias.

Examples of Disqualifying Bias:
-   Pecuniary and proprietary interests of the decision maker or a close family member in the outcome
-   Association with one of the parties relevant to the issues
-   Prejudgment of the issues or credibility
-   Hostility to one of the parties
-   Personal prejudice
-   Prosecutor acting as adjudicator
-   Procedure (e.g. Over-intervention in proceedings, hearing one party behind the back of the other without disclosure;  accuser having greater access to the decision maker than the accused)

8.1 Pecuniary Interest

-   Prior to Ebner there was automatic disqualification on proof of a direct, personal and more-than-trivial pecuniary or proprietary interest (in the outcome).
-   This shift is succinctly summarised by Kirby in Hot Holdings at 60 (p79 SR)
-   Note Kirby disagreed with this shift in Hot Holdings  “both as a matter of adherence to established legal authority and as a matter of legal principle and policy, I disagreed with the decision to depart from the rule in Dimes … recognising the “special class” of disqualification where there is “direct pecuniary interest in the outcome of the proceedings”. Ebner, so far as it concerns the recusal of judges and like decision-makers, puts Australia at odds with the strict law and practice observed, in this regard, in other common law countries. It does so at a time when there are strong reasons of legal policy for adhering to the strict and separate rule”

Eber v Official Trustee in Bankruptcy (2000) 176 ALR 644

PRINCIPLE: Pecuniary interest alone will not equate to automatic disqualification. In the case of ownership of shares, it must be ascertained whether the outcome of the litigation could have an effect on the judge’s financial interest.

-   There is no separate and free-standing rule of automatic disqualification for direct pecuniary or proprietary interest (as existed in Webb v Queen, R v Gough, HL in Pinochet (No 2); Dickason v Edwards)  rejected because “in its possible application to relatively common situations, its meaning is unclear”: Ebner
-   Instead – need to apply the “reasonable apprehension test”
-   The circumstances that a judge has a “pecuniary interest” in the outcome will result in disqualification on the reasonable apprehension test.

Held: GLEESON CJ,  McHUGH, GUMMOW, HAYNE JJ:
-   There is a fundamental principle that court cases, civil or criminal, must be decided by an independent and impartial tribunal  Bias, whether actual or apprehended connotes the absence of impartiality
-   In Webb v Queen, Deane J identified 4 distinct though overlapping categories of cases involving disqualification by reasons of appearance of bias  interest, conduct, association and extraneous information [convenient frame of reference]
-   There is no justification for having different principles for interest and association
-   In each case ... the question must be how it is said that the existence of the “association” or “interest” might be thought (by the reasonable observer) possibly to divert the judge from deciding the case on its merits … the bare identification of an “association” will not suffice to answer the relevant question. [especially given that “ownership, direct or indirect, of shares in a corporation is but one possible form of association with, and potential interest in, a litigant or a case”]
-   In the practical application of the test of apprehended bias, financial conflicts of interest are likely to be of particular significance [often more concrete in nature than other interests, and when the primary facts are known, easier to identify / public perception that they are more insidious than other forms of interest in their likely effect upon impartiality]
-   The primary factual consideration [whether there was a realistic possibility that the outcome of the litigation would affect the value of the relevant judge’s shareholding in the bank] – was a relevant factual consideration and not the ultimate test
Noted that the nature of the judge’s association with a litigant may be more complicated, as in Pinochet (No 2) and the possible effect of the outcome of a case upon the value of assets owned by a judge may be a matter of serious difficulty.
-   However, in the ordinary case where a judge owns shares in a listed company which is a party to, or is otherwise affected by, litigation, and there is no other suggested form of interest or association, the question whether there is a realistic possibility that the outcome of the litigation would affect the value of the shares will be a useful practical method of deciding whether a fair-minded observer might hold the relevant apprehension
-   If have a financial interest in the outcome, apprehension of bias rule will disqualify judge. But where it is that a clear outcome of a case would have no bearing on value of shares (court determines this on the facts) and there is no other suggested pecuniary interest, the judge will not be found to have a pecuniary interest.
-   Rejected the submission that there is a separate and free-standing rule of automatic disqualification which applies where a judge has a direct pecuniary interest, however small, in the outcome of the case over which the judge is presiding
-   Note: that the failure of the judge to disclose his acquisition of shares in the Bank was of no legal consequence  his silence could not reasonably support an inference of want of impartiality

The content of the rules requiring a fair and unbiased hearing are immensely flexible and provide no sure guide to action. They do not require ‘court-like’ proceedings.

Fair hearings may be conducted on the papers, the person who decides does not always have to conduct the hearing, rules of evidence do not apply to administrative decision-makers, and refusal of cross-examination or legal representation is not as a general rule a denial of procedural fairness.  It depends on what fairness requires in the particular circumstances.