45On the approach the appellants take, the term of mutual trust and confidence, as a term implied by law, is a legal incident of every employment contract, regardless of any presumption about the parties' intention. The implied term will therefore fail to operate in a particular case only if it is overriden by the parties themselves or if exclusion is otherwise indicated by "the circumstances of the making of the contract". These are words used by Jacobs J in Helicopter Sales (Aust) Pty Ltd v Rotor-Work Pty Ltd [1974] HCA 32; (1974) 132 CLR 1 at 17. And as Hope JA said in Castlemaine Tooheys Ltd v Carlton & United Breweries Ltd (1987) 10 NSWLR 468 at 492, the question of exclusion of a term implied by law is to be addressed by reference to the particular contract and the actual circumstances, not contracts of a class and general circumstances.
46The party who seeks to rely on the term must show that the contract is of the relevant class so as to attract the concern that the implication by law is intended to allay, that is, that rights conferred by contracts of the class will otherwise be undermined: Concrete Pty Ltd v Parramatta Design & Developments Pty Ltd [2006] HCA 55; (2006) 229 CLR 577 at [59]. Any competing contention that the implication is excluded must come from the party against whom the implication is pleaded: it is "still open to the defendants to show such a state of facts as will exclude the implication" Delohery v Permanent Trustee Co of NSW [1904] HCA 10; (1904) 1 CLR 283 at 314.
47In the present case, the respondent says that such a state of facts is found in the whole of the statutory context in which the appellants' contracts were made. The proposition advanced by the respondent is that the legislation governing the appointment and tenure of officers of the Education Teaching Service of New South Wales is so detailed and comprehensive that there is no room for the operation of any term of mutual trust and confidence. The necessity that is the source of the implication is said, for that reason, to be absent. What I have termed the "triable quality" of the appellants' case based on the implied term therefore depends on a finding that that proposition is incorrect.
48This leads to further consideration of the decision in McDonald. After reaching the conclusion already noticed regarding the implied term, the Full Court of the Supreme Court of South Australia proceeded to consider whether the implication was excluded by the circumstances of the particular case. In doing so, it embarked upon a detailed analysis of the statutory provisions governing the employment of teachers in the State's schools.
49The court noted (at [269]) that such employment was "heavily regulated by statute, regulation and by binding industrial instruments". Particular reference was made to extensive provisions for involvement by teachers in decision-making and policy development within schools and for appeal and review in relation to almost any matter about which a teacher may be aggrieved, including appeal against any decision involving termination of employment and against classification decisions, promotion decisions and any other decisions in respect of which they considered that they had just cause of complaint. There were also well-developed dispute resolution and grievance procedures.
50The analysis of the statutory scheme led the court to a conclusion stated in this way (at [270]):
"In our opinion, the statutory and regulatory context in which Mr McDonald's contract of employment operated made the implication of a term concerning mutual trust and confidence unnecessary."
51And then:
"The statutory and regulatory framework itself provided restraints on the exercise of power by the Minister and by those exercising supervisory or other powers under the Education Act which could affect Mr McDonald adversely. The existence of the means of redress can be taken to operate as a normative influence on the behaviour of the Minister and of others in positions of responsibility. Teachers are provided with means of redress in those cases in which powers are exercised unfairly, or are perceived to have been exercised unfairly. In this way, teachers such as Mr McDonald obtain the kind of protection to which, as we understand it, the implied term as to mutual trust and confidence is directed. The statutory and regulatory context in which Mr McDonald was employed provided, by a variety of means, for the achievement of a balance between the Minister's interests in discharging the obligations imposed by the Education Act and the teacher's interests in not being unfairly or improperly treated."
52Another basis for a like conclusion was then stated (at [271]):
"We appreciate that it could be said that the remedies which the Education Act, the Education Regulations, the industrial awards and the Certified Agreement provided to Mr McDonald do not preclude the implication of a term relating to mutual trust and confidence but instead simply provide part of the context to be considered in the event that recourse is had to those remedies. However, such an approach would mean that the necessity for the implication of the term would have to be found in other circumstances. It is not easy to identify such other circumstances. We do not consider that the relationship between implied term and the statutory award context of Mr McDonald's employment should be rationalised in this way."
53In the result, it was held that, in the particular statutory context, the implied term did not operate. The necessity that is the foundation of the implication was absent.
54The South Australian court proceeded on the same basis as the House of Lords in Johnson. The main claim of the employee in Johnson was for financial loss flowing from a psychiatric condition alleged to be a consequence of the unfair manner of his dismissal. He sued for damages for breach of the implied term of trust and confidence. The House of Lords examined statutory provisions under which an industrial tribunal could award "such amount as the tribunal considers just and equitable in all the circumstances having regard to the loss sustained by the complainant in consequence of the dismissal in so far as that loss is attributable to action taken by the employer". It was held, by majority, that implication of a term of mutual trust and confidence would be contrary to the evident intention of Parliament that the plaintiff's loss should be compensated, if at all, through the statutory process. That process applied to a particular class of persons, entailed a limit on sums recoverable and depended upon decision making by a specialist tribunal. Again, the necessity that is the foundation of the implication was absent.
55A different conclusion was reached in Lennon v State of South Australia [2010] SASC 272. It was there held that the implied term of trust and confidence formed part of the employment contract of a senior civil servant. Layton J acknowledged (at [177]) that there was "ample authority to support that a term of mutual trust and confidence can be implied into employment contracts at law". The point of distinction from McDonald was then explained (also at [177]):
"Having regard to the statutory context of the plaintiff's employment, I consider that the PSM Act [Public Sector Management Act 1995 (SA)] is not a regulatory framework of the kind described in McDonald. Section 12 of the PSM Act sets out the situations in which the contract may come to an end, but it is silent on the manner in which the parties are to conduct themselves towards each other and it provides no avenue for appeal in the case of a disappointed employee. Whilst there may have been at one time, a technical possibility for the plaintiff to bring judicial review proceedings of a decision by the Government (or one of its agents), I do not consider this to be the sort of "means of redress" to which the Court was referring in McDonald. It must be remembered that even if judicial review was possible, it does not provide the same sort of protection and regulation as did the scheme in McDonald nor the same remedies as are sought in this case. I conclude that a term of mutual trust and confidence is implied in law in the plaintiff's contract of employment."
56In the present case, the respondent pointed to very significant similarities between the South Australian legislation considered in McDonald and the New South Wales legislation in force when the appellants were officers of the Education Teaching Service of New South Wales. It is unnecessary to go into detail. It is sufficient to note that a table comparing the legislation of the two States provided to the court by the respondent (and agreed by the appellants) showed that every provision of any consequence in force in South Australia at the time relevant to the McDonald decision had a clear counterpart in New South Wales at the time relevant to these proceedings.
57Assuming that McDonald is correct (a matter on which it is unnecessary to express any concluded view), it is distinguishable because of one notable difference between the circumstances under consideration there and those of this case. It comes from a feature of the New South Wales statutory provisions that had no counterpart in South Australia. The appellants held probationary appointments, a species of tenure not provided for in the South Australian legislation. They were therefore governed by s 48 of the Teaching Service Act which, as in force at the relevant time, was in these terms:
"(1) Unless the Director-General of Education, in a particular case or class of cases, otherwise determines, a person who is not an officer of the Education Teaching Service when the person is appointed by the Director-General to a permanent position in that service shall be appointed on probation, which shall be for a period of 12 months or such longer period as the Director-General may in any particular case or class of cases determine.
(2) The Director-General of Education may:
(a) after the expiration of the period of probation for which a person is so appointed, confirm or annul the appointment, or
(b) during the period of probation for which a person is so appointed, extend the period of probation or annul the appointment.
(3) Where the appointment of a person is so annulled, the person shall thereupon cease to be employed under this Division as an officer of the Education Teaching Service and shall, unless the Director-General of Education makes a determination under subsection (4), be deemed to be a temporary employee of the Education Teaching Service under this Act.
(4) Where the appointment of a person is so annulled, the Director-General of Education may determine that the person shall cease to be employed in the Education Teaching Service upon a day specified in the determination and the person shall cease to be so employed on that day.
(5) A person who, by reason of the annulment of an appointment, ceases to be a member of the Education Teaching Service under this section is not entitled to appeal to the Government and Related Employees Appeal Tribunal against the annulment or against any determination of the Director-General made under subsection (4).
(6) Nothing in section 85 prevents the Director-General of Education from exercising, at any time, the power to annul an appointment under subsection (2).
(7) This section does not apply to the appointment of a senior executive officer to a position in the Education Teaching Service."
58Annulment of the appointment of each appellant was made under s 48(2). The date specified pursuant s 48(4) was, in each case, 20 March 2000. Because of their probationary status and the deployment against them of the annulment process, the appellants ceased to be Crown employees (and members of the Education Teaching Service) on 20 March 2000 and were denied by s 48(5) access to appeal procedures in respect of both the annulment and every associated determination. In addition, the effect of s 48(6) was to make inapplicable provisions of s 85 under which involuntary separation might be achieved by enforced or negotiated resignation as an alternative to dismissal (or annulment).
59Certain protective incidents favourable to employees that formed part of the regime applicable to other teachers thus did not apply to the appellants as probationary employees. The denial of the favourable incidents means one of two things: that effect must simply be given in an unqualified way to a statutory intention that their employer may treat persons of the relevant kind in a way that is, by comparison, disadvantageous; or that the absence of the protective incidents in relation to those persons leaves, in those respects, a gap in the statutory coverage that allows potential scope for the operation of the implied term of mutual trust and confidence.
60The correctness of the latter approach rather than the former is, in my opinion, arguable with sufficient cogency to establish the triable quality of the proposition that the implied term forms part of the appellants' contracts. There is a plausible basis for arguing that the gap in the statutory coverage in relation to probationary teachers is of the kind that caused Layton J to conclude in Lennon v South Australia that the implied term applied. All-embracing statutory substitutes of the kind on which the decision in Johnson turned are arguably absent.
61In Paige, Spigelman CJ referred (at [150]) to the statutory arrangements concerning dismissal of New South Wales teachers, including the availability of unfair dismissal proceedings, and saw the existence of those arrangements as a reason for not recognising "a parallel remedy of unlimited scope " at common law. The exceptions affecting probationary teachers are arguably sufficient to render that thinking inapplicable to this case.