Commonwealth Common-Law Contract Law (LLB Academic Unit)

# Commonwealth Common-Law Contract Law — Study Notes

GROUNDED (web-sourced from free-access law: AustLII (austlii.edu.au)) - citations real but not cross-checked against our DB; verify before deploy.

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## Part 1: Formation of Contract (25%)

### Offer: Definition, Invitation to Treat, Termination

An **offer** is a definite promise made by one party (offeror) to another (offeree), with the intention that it shall become binding as soon as it is accepted.

**Key Distinction**: Distinguish offers from invitations to treat (e.g. goods displayed in a shop window), which are merely invitations to others to make offers.

**Real Case Authority**:
- *Carlill v Carbolic Smoke Ball Co* [1892] EWCA Civ 1; [1893] 1 QB 256. The defendant company advertised a £100 reward for anyone contracting influenza after using their smoke ball, stating they deposited £1,000 in a bank to show good faith. The plaintiff purchased and used the product, contracted influenza, and sued for the promised reward. **Principle**: A unilateral offer (reward for an act) is a true offer capable of acceptance by performance of the stipulated condition. Advertisement of such an offer is not mere puffery or invitation to treat, but a definite promise provided the advertiser manifests clear intent to be bound. This is a foundational case for understanding offer formation when the offeree does not need to communicate acceptance.

**Termination of Offer**: An offer may be terminated by rejection, counter-offer, lapse of time, revocation by the offeror (if communicated), or death of either party (depending on jurisdiction).

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### Acceptance: Mirror-Image Rule, Communication, Silence

**Acceptance** is an unqualified assent to the offeror's proposed terms.

**Mirror-Image Rule**: Common law requires that acceptance must conform exactly to the offer's terms. Any departure creates a counter-offer, which rejects the original offer.

**Communication of Acceptance**: Acceptance must generally be communicated to the offeror, either expressly or by conduct consistent with acceptance. Acceptance is usually effective only once communicated and received.

**Silence as Acceptance**: As a general rule, silence does not constitute acceptance, even if the offeror states that failure to respond will be treated as acceptance. However, acceptance may be implied from the offeree's conduct (e.g. using goods or services).

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### The Postal Rule (Adams v Lindsell)

**Citation**: Adams v Lindsell (1818) 1 B & Ald 681; [106 ER 250].

**Principle**: Where the parties contemplate that acceptance will be communicated by post, acceptance becomes effective when the letter of acceptance is **posted** (placed in the mail), not when it is received by the offeror. This is an exception to the general rule requiring communication to the offeror.

**Real Case Authority**:
The postal rule was established to resolve the problems caused by postal delays. Where both parties envisage use of the post, the offeror is deemed to have accepted the risk of loss or delay in transit. The rule applies only if the post is a reasonable or contemplated mode of communication, and applies to acceptance only (not to revocation of an offer or rejection of an acceptance).

**Modern Application**: In contemporary contract law, the postal rule is narrower in scope. It applies primarily to traditional mail and may not extend to instantaneous methods of communication like telex or email, which are subject to the **reception rule** (acceptance is effective only upon receipt).

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### Unilateral Contracts and Advertisement Offers

**Unilateral Contract**: A contract in which one party (offeror) makes a promise, and the other party (offeree) accepts by performing a specified act, rather than by making a return promise.

**Real Case Authority**: 
- *Carlill v Carbolic Smoke Ball Co* [1892] EWCA Civ 1; [1893] 1 QB 256 (detailed above). The case established that an advertisement of a unilateral offer can be a binding offer if the offeror manifests clear intent to be bound and the terms are sufficiently definite. The requirement for acceptance is not a communication but performance of the condition stipulated.

**Key Distinction**: In a unilateral contract, the offeree need not communicate acceptance. Acceptance occurs upon completion of the requested act. The offeror's posting of the offer is a standing offer to anyone who performs the condition.

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### Battle of Forms (Butler Machine Tool)

**Citation**: Butler Machine Tool Co Ltd v Excello Corporation (Engineering) Ltd [1979] 1 WLR 401 (English Court of Appeal).

**Scenario**: Two businesses exchange purchase orders and acknowledgements, each with different standard terms on the reverse. The question is: whose terms govern the contract?

**Real Principle** (from Commonwealth case law):
The last shot doctrine applies in many Commonwealth jurisdictions: the contract is formed on the terms of the **last document sent before performance or acceptance**, provided that document clearly asserts that its terms supersede any previous offer or counter-offer. However, this approach is problematic and courts prefer to look at the parties' conduct to discern a common intention to be bound.

**Modern Approach**: Courts look to whether:
1. There is agreement on essential terms (price, goods, delivery);
2. Each party's conduct indicates assent to the other's terms;
3. Which party's standard terms were last presented and accepted by performance.

If there is no clear agreement on all terms, the court may find no concluded contract, or may imply the reasonable terms the parties must have intended.

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### Intention to Create Legal Relations

**Principle**: Parties must manifest an intention to create legal relations (not merely social or domestic arrangements). This is determined objectively by reference to the reasonable person's interpretation of the parties' conduct and language.

**Presumptions**:
- **Commercial agreements**: Presumed to create legal relations unless rebutted by clear evidence.
- **Domestic or social agreements**: Presumed NOT to create legal relations unless rebutted by evidence of clear intent.

Example: An agreement between family members to share household expenses is not normally enforceable at law unless it is expressed in language that shows a clear intention to be legally bound.

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## Part 2: Consideration (20%)

### Past Consideration Rule

**Principle**: Past consideration is generally **not valid** consideration for a new promise. Consideration must move from the promisee to the promisor as part of the bargain for the new promise, and must be given in exchange for the promise.

**Definition**: Past consideration is an act or forbearance performed **before** the promise was made, and not referable to the promise. If you have already done something before the other party makes a promise, your prior act cannot be consideration for that promise.

**Example**: If a builder completes a house and the owner then promises to pay a bonus, the completion of the house is past consideration and the owner's promise is not enforceable (unless there was an agreement to pay before completion, or unless there are other grounds like promissory estoppel).

**Exception**: Some jurisdictions recognise a limited exception where the past act was done at the request of the promisor and both parties understood that payment would follow.

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### Existing Duty Rule (Stilk v Myrick)

**Citation**: Stilk v Myrick (1809) 2 Camp. 317; [170 ER 851].

**Facts**: A sea captain promised extra wages to sailors who would work the voyage home after desertion of crew members. The sailors sued for the extra wages.

**Principle**: A promise to perform (or performance of) a pre-existing duty owed to the promisor does **not** constitute valid consideration for a new promise by the promisor. If you are already contractually bound to do X, a promise to pay you extra to do X is not supported by consideration—you are merely performing your existing obligation.

**Application**: This rule prevents opportunistic behaviour where a party threatens to breach a contract unless the other party agrees to pay more.

**Real Commonwealth Authority**:
The existing duty rule is foundational in Commonwealth contract law and has been applied consistently across England, Australia, Canada, and other jurisdictions. It protects the original bargain from being renegotiated under duress.

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### Practical Benefit Doctrine (Williams v Roffey Bros)

**Citation**: Williams v Roffey Bros & Nicholls (Contractors) Ltd [1990] 1 WLR 1153 (English Court of Appeal).

**Facts**: Main contractors hired a carpenter to perform carpentry work on a residential development. The carpenter ran into financial difficulties and could not continue. To avoid penalties for late completion and the expense of hiring replacement workers, the main contractors promised the carpenter extra payment in exchange for continued performance.

**Principle**: Even though performance of the carpenter's existing duty might not ordinarily constitute consideration, the courts recognised that the main contractors obtained a **practical benefit** from the arrangement: avoiding penalties, avoiding the trouble and expense of engaging alternative workers, and maintaining the schedule. These practical benefits, being part of the bargain for the extra payment, could constitute consideration.

**Real Commonwealth Authority**:
*Williams v Roffey Bros & Nicholls (Contractors) Ltd* [1990] 1 WLR 1153 marks a significant departure from strict application of Stilk v Myrick. The practical benefit doctrine has been accepted and routinely applied across Commonwealth jurisdictions, including Australia and other common law countries, with endorsement from appellate courts.

**Limitations**: Courts apply this doctrine cautiously. There must be:
1. A genuine practical benefit to the promisor;
2. No economic duress or illegitimate pressure;
3. A clear intention by both parties that the new promise is binding.

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### Sufficiency vs Adequacy of Consideration

**Sufficiency**: Courts ask whether something of legal value has passed from promisee to promisor. Consideration must be real, not sham.

**Adequacy**: Courts **do not police the fairness** of the bargain. Even if the consideration is grossly inadequate (e.g. paying £1 for goods worth £100), the contract remains enforceable, provided the promisee provided something of legal value in exchange.

**Principle**: The law assumes that parties are free to make bad bargains. The court's role is not to remedy one-sided bargains, but to ensure that some consideration was given.

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### Promissory Estoppel / Pinnel's Case

**Citation - Foundational English Rule**: Pinnel's Case (1602) 5 Co. Rep. 117a (established the rule against part-payment of debt as discharge).

**Principle**: Payment of a lesser sum cannot discharge a debt of a greater sum. If you owe £100 and pay £80 in full settlement, the creditor is not bound to forgo the remaining £20.

**Equitable Estoppel—Modern Exception**:
Commonwealth courts (particularly in Australia and following the English Court of Appeal) have recognised that **promissory estoppel** can prevent a creditor from enforcing the full amount if:
1. The creditor has made a clear and unequivocal promise to accept the lesser amount;
2. The debtor has relied on that promise to their detriment;
3. It would be inequitable for the creditor to withdraw the promise.

**Real Commonwealth Authority**:
*Waltons Stores (Interstate) Ltd v Maher* [1988] HCA 7; (1988) 164 CLR 387 (Australian High Court). The High Court significantly broadened the doctrine of promissory estoppel, holding that estoppel can apply even where there is no pre-existing contractual relationship. The court recognised six elements: the plaintiff's assumption that a legal relationship would be created or modified; the defendant's inducement of that assumption; the plaintiff's reliance on the assumption; the plaintiff's conduct in reliance on the assumption; detriment to the plaintiff from the defendant's behaviour; and the defendant's knowledge of the assumption and that the plaintiff is relying upon it.

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## Part 3: Contractual Terms and Certainty (15%)

### Certainty and Completeness (Scammell v Ouston)

**Citation**: G Scammell and Nephew Ltd v H. C. and J. G. Ouston [1941] A.C. 251 (English House of Lords).

**Principle**: For a contract to be enforceable, its terms must be **sufficiently certain**. A court must be able to identify the essential terms (price, goods, delivery) with sufficient clarity to enforce the agreement.

**Real Commonwealth Authority**:
The House of Lords held that where the language of a contract is uncertain such that a court cannot ascertain the parties' rights and obligations with sufficient precision, no concluded contract will be found. Courts will not fill in major gaps or remake the contract for the parties.

**Application**: If essential terms remain to be negotiated or agreed, there is no binding contract. However, courts will uphold contracts that contain minor vague provisions if the parties clearly intended to be bound and if there is a reasonable mechanism to resolve the ambiguity.

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### Express vs Implied Terms

**Express Terms**: Terms explicitly stated by the parties in writing, orally, or by conduct.

**Implied Terms**: Terms not expressed but read into the contract by:
1. **Custom or trade usage**: Terms implied by the normal understanding in a particular industry or trade.
2. **Necessity**: Terms implied because they are necessary to give the contract business efficacy or to reflect the parties' presumed common intention.
3. **Statute**: Many statutes (Sale of Goods Act, Consumer Rights Act) imply terms into contracts for the supply of goods or services (e.g. fitness for purpose, satisfactory quality).

**Real Commonwealth Authority**:
The principle that courts will imply reasonable terms necessary to give the contract effect is well-established across Commonwealth jurisdictions. However, courts are reluctant to imply terms and will not do so if the express terms of the contract are inconsistent with the implied term.

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### Conditions, Warranties, Innominate Terms

**Condition**: A term so essential to the contract that breach of it goes to the root of the agreement. Breach of a condition entitles the innocent party to:
1. Reject the goods/refuse performance;
2. Claim damages.

**Warranty**: A lesser term, not going to the root of the agreement. Breach of a warranty entitles the innocent party only to claim damages, not to reject the goods or refuse further performance.

**Innominate (or Intermediate) Terms**: Terms that may be either conditions or warranties depending on the **consequences of the breach**. If the breach deprives the innocent party of substantially the whole benefit of the contract, the term is treated as a condition; if not, it is treated as a warranty.

**Real Commonwealth Authority**:
This classification is standard across Commonwealth contract law and has been applied in Australian, Canadian, and other jurisdictions. The concept of innominate terms was developed in English law and has been adopted widely.

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### Exclusion and Limitation Clauses (UCTA / Incorporation)

**Exclusion Clauses**: Terms that attempt to exclude or limit liability for breach of contract or negligence.

**Incorporation**: Before an exclusion clause can be effective, it must be **incorporated** into the contract. Methods of incorporation include:
1. **Signature**: Signing a document containing the clause.
2. **Notice**: Bringing the clause to the other party's attention with reasonable prominence (e.g. display in a shop, reference in a ticket).
3. **Course of dealing**: A consistent prior course of dealing between the parties.

**Interpretation Against the Drafter**: Exclusion clauses are **construed strictly** against the party who relied on them (contra proferentem rule). Ambiguities are resolved in favour of the other party.

**Statutory Control—Unfair Contract Terms Act 1977 (UCTA)**:
The UCTA and its successor, the Consumer Rights Act 2015, impose statutory restrictions on the enforceability of exclusion and limitation clauses:

1. **Liability for negligence**: Cannot be excluded if it causes death or personal injury; for other loss, exclusion must be reasonable.
2. **Sale of goods**: Exclusion of liability for breach of implied terms (title, description, quality, fitness) is effective only if it satisfies the reasonableness test in commercial transactions; it is wholly ineffective for consumer transactions.
3. **Reasonableness Test**: A clause is reasonable if it was a fair and reasonable one to include in the contract, having regard to the circumstances known or reasonably contemplated at the time of contracting.

**Real Commonwealth Authority**:
Exclusion clauses are recognised and enforced across Commonwealth jurisdictions, subject to the same principles of incorporation, strict construction, and statutory reasonableness tests. The UCTA is the primary English statute; Australia, Canada, and other Commonwealth countries have parallel consumer protection legislation with similar principles.

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### Parol Evidence Rule

**Principle**: Where the parties have reduced their agreement to a **final written form**, evidence of prior oral or written negotiations, statements, or agreements **cannot be used to vary, contradict, or supplement** the written terms.

**Rationale**: Once a contract is in writing, the written document is the best evidence of what the parties agreed. Allowing extrinsic evidence would undermine the certainty of written contracts.

**Exceptions**: The rule does not prevent evidence of:
1. Fraud, duress, or misrepresentation;
2. The validity of the written agreement itself;
3. Conditions **precedent** to the written document (i.e. conditions that must be satisfied before the written agreement comes into force);
4. Implied terms (as discussed above);
5. Subsequent oral modifications (though these may themselves be subject to the rule if a written contract provides for no oral variations).

**Real Commonwealth Authority**:
The parol evidence rule is a fundamental principle of Commonwealth contract law, derived from English common law. It applies across all Commonwealth jurisdictions but is narrowly construed to protect the primacy of the written agreement where the parties have clearly indicated that the writing is their final agreement.

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## Part 4: Vitiating Factors / Defences to Formation (20%)

### Misrepresentation (Fraudulent, Negligent, Innocent)

A **misrepresentation** is a false statement of fact made by one party, which induces the other party to enter the contract.

**Elements**:
1. A statement (or conduct) that contains a false assertion of fact;
2. The statement induced the innocent party to enter the contract;
3. The innocent party relied upon the statement.

**Types**:

**1. Fraudulent Misrepresentation** (Deceit)
- The representor knew the statement was false, or was reckless as to its truth.
- Remedy: Rescission of the contract + damages for the tort of deceit.
- Real Commonwealth Authority: Common law remedy available across all Commonwealth jurisdictions; derived from foundational English cases.

**2. Innocent Misrepresentation**
- The representor made the false statement believing it to be true, but there were no reasonable grounds for that belief.
- Remedy at common law: Rescission only (no damages), subject to loss of the right to rescind if affirmed or if substantial damages would be inadequate.
- Statutory Reform: The Misrepresentation Act 1967 (UK) and equivalent statutes in other Commonwealth jurisdictions allow damages in lieu of rescission even for innocent misrepresentation, if damages are appropriate.

**3. Negligent Misrepresentation**
- The representor made the false statement without reasonable care or diligence, or carelessly without sufficient grounds to warrant its truth.
- Remedy: Damages under the Misrepresentation Act 1967 (or equivalent); party is liable unless they can prove they had reasonable grounds to believe the statement was true.

**Real Commonwealth Authority**:
The three-part classification and the statutory remedies under the Misrepresentation Act 1967 are standard across Commonwealth contract law. Parallel legislation exists in Australian states, Canada, Singapore, and other jurisdictions.

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### Duress (Economic Duress)

**Duress** is a vitiating factor allowing a party to set aside a contract entered under illegitimate pressure or coercion.

**Traditional Duress** (Duress to the Person):
- Actual or threatened violence to the person.
- Clearly vitiates consent to contract.

**Economic Duress** (Duress of Goods / Business Compulsion):
- Economic pressure or threat used to procure a contract or payment.
- Real Commonwealth Authority:
  - *Pao On v Lau Yiu Long* [1980] AC 614 (Privy Council). The Privy Council accepted that economic duress may be recognised in common law. The Board identified two elements: (i) the existence of pressure amounting to compulsion of the will of the victim; (ii) illegitimacy of the pressure exerted.
  - *The Universe Sentinel* [1983] 1 AC 366 (Privy Council). A case involving economic duress where shipowners alleged a contract was obtained under duress through union "blacking" that prevented the ship from leaving port.
  - *Atlas Express Ltd v Kafco Importers and Distributors Ltd* (1989) 3 WLR 389 (English Court of Appeal). A case addressing economic duress as a vitiating factor.

**Test for Economic Duress**:
1. There is pressure from the defendant;
2. The pressure is illegitimate (e.g. breaching a statutory duty, threatening breach of contract, or economic pressure not justified by business circumstances);
3. The pressure is of a nature and degree such that it compels the victim's unwilling assent;
4. The victim protested the pressure or sought to avoid it;
5. The victim gave notice of its intention to disaffirm the contract.

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### Undue Influence

**Undue Influence** is where a person is induced to enter a contract by improper pressure or manipulation by another, exploiting a relationship of trust or dominance.

**Real Commonwealth Authority**:
Undue influence is a well-established equitable doctrine across Commonwealth jurisdictions. The doctrine recognises two classes:

**Class 1: Actual Undue Influence**
- Direct evidence of improper pressure or persuasion used by the defendant to procure the contract.
- The claimant must prove actual undue influence.

**Class 2: Presumed Undue Influence**
- Certain relationships (trustee–beneficiary, solicitor–client, parent–young child, religious advisor–follower) give rise to a **presumption of influence**. If a transaction is unexplained and manifestly disadvantageous, influence is presumed and the burdened party must rebut it by proving the transaction was free and fair.
- Manifest disadvantage is required (i.e. the transaction is so clearly disadvantageous that it suggests the party did not exercise independent judgment).

**Remedy**: Rescission (setting aside the contract) and restitution of benefits received.

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### Mistake (Common, Mutual, Unilateral)

**Common Mistake**:
- Both parties are mistaken about the same fact (e.g. both believe goods exist when they do not).
- Generally, does not void the contract at common law unless it is fundamental to the transaction (e.g. both parties believe the contract concerns goods that do not exist).
- Equity may grant rescission if the mistake is fundamental, though this is narrowly construed.

**Mutual Mistake**:
- The parties are at cross-purposes—each party intends something different.
- If the true positions are ambiguous and both interpretations are reasonable, no contract is formed. If one interpretation is clearly unreasonable, the other party's understanding prevails.

**Unilateral Mistake**:
- Only one party is mistaken about a fact.
- Generally does not vitiate the contract, except in narrow cases:
  1. **Mistake as to identity**: In some contexts, if the innocent party is fundamentally mistaken about the identity of the other party (e.g. a fraudster assumed a false identity), the contract may be void.
  2. **Mistake apparent on the face of the document**: If the written contract contains an obvious clerical error, the court may rectify the document to reflect the parties' true intent.

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### Illegality and Public Policy

**Illegality**: A contract may be void or unenforceable if:
1. It requires performance of an act that is illegal (criminal or tortious);
2. It is prohibited by statute;
3. It is contrary to public policy (e.g. contracts that oust the jurisdiction of the courts, restrict personal freedom unreasonably, or are sexually immoral or involve fraud).

**Real Commonwealth Authority**:
Illegality and public policy defences are recognised across Commonwealth contract law. Courts apply a doctrine of **strict scrutiny**: they will not enforce contracts that contravene law or fundamental public policy, but will not lightly extend the doctrine of illegality to defeat the parties' bargain without clear legal prohibition or strong public policy grounds.

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## Part 5: Privity of Contract (5%)

### Privity Rule and Exceptions

**Privity of Contract**: A fundamental principle that only the parties to a contract have rights and obligations under that contract. Third parties cannot sue or be sued on the contract, even if the contract is intended for their benefit.

**Real Commonwealth Authority**:
The privity rule is well-established in English law and followed across Commonwealth jurisdictions. However, it has been subject to significant statutory and equitable modification.

**Exceptions to Privity**:

1. **Contracts (Rights of Third Parties) Act 1999 (UK)** and equivalent statutes in other Commonwealth jurisdictions allow a third party to enforce the contract if:
   - The contract expressly states that the third party has a right to enforce;
   - The contract purports to confer a benefit on the third party and it is clear that the parties intended the third party to have a right to enforce.

2. **Equitable doctrine of trusts**: If A contracts with B for the benefit of C, and B holds the contract benefit in trust for C, then C may enforce the contract through the trustee.

3. **Collateral warranties**: A statement made before or at the time of contracting may be a collateral contract if it induces the third party to enter the main contract.

4. **Agency**: If A contracts as an agent for B (an undisclosed principal), B may enforce the contract.

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### Contracts (Rights of Third Parties) Act 1999

**Scope**: This Act (1999 c. 31 (UK)) permits a third party to enforce a contract if:
1. The contract expressly provides that the third party may enforce it;
2. The contract purports to confer a benefit on the third party and it is reasonable to conclude that the parties intended the third party to have the right to enforce.

**Real Commonwealth Authority**:
The Act represents a major departure from the strict privity rule and has been adopted or paralleled in many Commonwealth jurisdictions. It provides a statutory mechanism for third-party beneficiaries to enforce contracts, subject to defences available between the original contracting parties.

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## Part 6: Discharge and Breach (8%)

### Material vs Immaterial Breach

**Breach of Contract**: A failure by one party to perform its obligations under the contract.

**Material Breach** (Repudiatory Breach):
- A breach that is so serious that it deprives the innocent party of substantially the whole benefit of the contract.
- Remedy: The innocent party may treat the contract as **discharged** (terminated) and claim damages for the loss of the entire contractual benefit, or may choose to continue performance and claim damages.

**Immaterial Breach**:
- A breach that does not significantly affect the innocent party's rights or the purpose of the contract.
- Remedy: The innocent party may only claim damages for the loss caused by the breach; cannot terminate the contract.

**Real Commonwealth Authority**:
The distinction between material and immaterial breach is foundational in Commonwealth contract law. Courts assess materiality by asking whether the breach destroys the essential purpose of the contract from the innocent party's perspective.

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### Repudiation / Anticipatory Breach

**Anticipatory Breach** (Repudiation):
- A party indicates, **before the time fixed for performance**, that it does not intend to perform its obligations.
- The innocent party may treat the anticipatory breach as a **present breach** and terminate the contract immediately, or may choose to wait for the actual breach date and claim damages.

**Real Commonwealth Authority**:
Anticipatory breach is recognised across Commonwealth contract law. The innocent party has the right to accept the repudiation and terminate, or to wait for the contractual performance date and treat the breach as occurring at that time.

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### Frustration and Force Majeure

**Frustration of Contract**:
- Where **unforeseen circumstances** occur after the contract is made, rendering performance impossible, illegal, or radically different from what was originally contemplated.
- Effect: The contract is **discharged** (terminated) by operation of law; both parties are relieved from further obligations.
- Real Commonwealth Authority:
  - *Taylor v Caldwell* (1868) L.R. 4 Q.B. 127 (English Court of Common Pleas). A foundational case where a concert hall burned down before the date of a scheduled concert. The court held that where unforeseen destruction renders performance impossible, the contract is discharged by frustration.
  - The doctrine has been consistently applied across Commonwealth jurisdictions (Australia, Canada, etc.), refined by subsequent case law to address situations where performance is impossible, illegal, or commercially radically different.

**Test for Frustration**:
1. An unforeseen event occurs after the contract is formed;
2. Performance becomes impossible, illegal, or radically more onerous/different;
3. The event was not the fault of either party;
4. The event was not foreseen or provided for in the contract;
5. The frustrating event destroys the basic purpose of the contract.

**Force Majeure Clause**:
- A contractual clause that excuses performance if specified events (wars, strikes, acts of God) occur.
- Force majeure clauses operate **contractually**; they supersede the common law doctrine of frustration to the extent the parties have expressly provided for the consequences of the frustrating event.

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### Discharge by Performance, Agreement, Operation of Law

**Discharge by Performance**:
- The contract is discharged when both parties have **fully performed** their obligations.
- Strict performance is required (must be complete and precise), except where substantial performance is accepted.

**Discharge by Agreement**:
- The parties may agree to **vary or rescind** the contract.
- Variation requires consideration (a new bargain); rescission (complete termination) does not.

**Discharge by Operation of Law**:
- **Frustration**: Discussed above.
- **Merger**: Where a contract is superseded by a deed (instrument under seal) covering the same subject matter.
- **Judgment**: Where one party obtains a court judgment for breach, the contract merges into the judgment.

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## Part 7: Remedies (7%)

### Damages: Expectation, Reliance, Restitution

**Expectation Damages**:
- Compensate the innocent party for the loss of the bargain.
- Award = the value of performance promised minus the value received.
- Goal: Put the innocent party in the position it would have been in had the contract been performed.
- Most common remedy in contract law.

**Reliance Damages**:
- Compensate the innocent party for losses incurred in reliance on the contract, even if the contract would not have been profitable.
- Award = actual expenditure incurred in reliance on the contract.
- Used when expectation damages are difficult to quantify (e.g. wasted expenditure).

**Restitution**:
- Recover benefits conferred on the breaching party where there is no legitimate basis for the breaching party to retain those benefits.
- Award = the value of the benefit received.
- Used where a contract has been partly performed and then breached.

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### Remoteness: Hadley v Baxendale Test

**Citation**: Hadley v Baxendale (1854) 9 Exch. 341; [156 ER 145] (English Exchequer Court).

**Facts**: The plaintiffs operated a mill. The crankshaft broke, and they hired the defendants (carriers) to deliver it to an engineer for repairs. The defendants delayed delivery, and the plaintiffs claimed damages for lost profits during the shutdown.

**Principle**: Damages must be reasonably foreseeable as a probable result of the breach at the time the contract was made.

**The Two Limbs of Hadley v Baxendale**:

**Limb 1**: Damages arising **naturally, according to the usual course of things** (the general or natural loss).
- These are foreseeable without special notice; e.g. for failure to deliver goods, the ordinary loss is the difference in value.

**Limb 2**: Damages **reasonably supposed to have been in the contemplation of both parties** at the time of contract as the probable result of breach.
- These are special damages foreseeable only if the innocent party gave notice of special circumstances; e.g. if the shipper told the carrier that the delay would halt a mill, the carrier then knows of the special loss and can be liable for it.

**Real Commonwealth Authority**:
Hadley v Baxendale is the foundational remoteness test in Commonwealth contract law. Applied consistently across England, Australia, Canada, and other jurisdictions. The test reflects a balance between protecting the innocent party and preventing the breaching party from becoming an insurer of all possible losses.

**Application**: A loss is too remote if the breaching party did not know, or could not reasonably have known, that the breach would cause that loss.

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### Mitigation Duty

**Principle**: The innocent party has a **duty to mitigate** the loss caused by the breaching party's breach. The innocent party must take reasonable steps to minimise loss and cannot recover damages for avoidable loss.

**Real Commonwealth Authority**:
The duty to mitigate is a fundamental principle across Commonwealth contract law. It reflects the principle that the innocent party should not sit back and allow losses to accumulate when reasonable action could prevent or reduce them.

**Application**: 
- If a supplier breaches a delivery contract, the buyer must seek alternative sources of goods or materials.
- If an employee is wrongfully dismissed, the employee must seek alternative employment.
- Failure to mitigate reduces the recoverable damages.

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### Liquidated Damages and Penalty Clauses

**Liquidated Damages Clause**: A term in the contract that specifies a pre-estimated sum payable in the event of breach.
- If the sum is a genuine pre-estimate of loss, it is **enforceable**.
- Courts uphold liquidated damages clauses if they represent a reasonable assessment of the anticipated loss, not a penalty.

**Penalty Clause**: A clause that imposes a sum disproportionate to the genuine loss anticipated by the parties.
- **Unenforceable**. Courts will not enforce a provision that is manifestly excessive and appears designed to punish the breaching party rather than compensate the innocent party.

**Test**: Courts ask whether the sum stipulated is (i) a genuine pre-estimate of loss, or (ii) a penalty out of proportion to the anticipated harm. If the sum is extravagant or unconscionable in relation to the actual loss, it is a penalty and unenforceable.

**Real Commonwealth Authority**:
The distinction between liquidated damages and penalties is recognised across Commonwealth contract law. The principle is that the law will not enforce provisions designed purely to punish a party, but will uphold genuine pre-estimates of loss.

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### Specific Performance and Injunction

**Specific Performance**:
- An equitable remedy that orders the breaching party to **perform the contract** (rather than just pay damages).
- Available where damages are inadequate compensation.
- Discretionary remedy; not available where:
  1. Damages are an adequate remedy;
  2. The contract involves personal services;
  3. The court cannot supervise compliance;
  4. The innocent party has delayed seeking the remedy (laches).
- Common in contracts for the sale of land or rare goods.

**Injunction**:
- An equitable remedy that orders a party to **refrain from doing something** (negative injunction) or to do something (positive injunction, less common).
- Used to prevent breach or continuing breach.
- Available where damages are inadequate and the court can frame a clear order.

**Real Commonwealth Authority**:
Specific performance and injunctions are equitable remedies available across Commonwealth jurisdictions. They are discretionary and granted only where necessary to protect the innocent party's interest in specific performance of the contract.

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### Rescission

**Rescission**:
- An equitable remedy that **sets aside the contract ab initio** (from the beginning), treating it as if it never existed.
- Available for vitiating factors: fraud, misrepresentation, duress, undue influence, mistake.
- Effect: Restores the parties to their pre-contractual positions.
- **Bars to Rescission**:
  1. **Affirmation**: The innocent party, with knowledge of the vitiating factor, continues to perform or treats the contract as valid.
  2. **Laches**: Undue delay in seeking rescission.
  3. **Third-party rights**: If an innocent third party has acquired rights under the contract, rescission may not be available.
  4. **Restitution impossible**: If the parties cannot be restored to their original positions (e.g. goods have been used), rescission may be refused.

**Real Commonwealth Authority**:
Rescission is a foundational equitable remedy in Commonwealth contract law. It is the primary remedy for misrepresentation, duress, and undue influence, available where the innocent party seeks to undo the contract and recover what was given.

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## Summary of Real Cases Cited

1. **Carlill v Carbolic Smoke Ball Co** [1892] EWCA Civ 1; [1893] 1 QB 256 — Unilateral contracts and offer.
2. **Adams v Lindsell** (1818) 1 B & Ald 681; [106 ER 250] — Postal rule.
3. **Butler Machine Tool Co Ltd v Excello Corporation (Engineering) Ltd** [1979] 1 WLR 401 — Battle of forms.
4. **Williams v Roffey Bros & Nicholls (Contractors) Ltd** [1990] 1 WLR 1153 — Practical benefit doctrine.
5. **Stilk v Myrick** (1809) 2 Camp. 317; [170 ER 851] — Existing duty rule.
6. **G Scammell and Nephew Ltd v H. C. and J. G. Ouston** [1941] A.C. 251 — Certainty of terms.
7. **Hadley v Baxendale** (1854) 9 Exch. 341; [156 ER 145] — Remoteness of damages.
8. **Waltons Stores (Interstate) Ltd v Maher** [1988] HCA 7; (1988) 164 CLR 387 — Promissory estoppel.
9. **Entores Ltd v Miles Far East Corporation** [1955] EWCA Civ 3; [1955] 2 QB 327 — Telex acceptance.
10. **Taylor v Caldwell** (1868) L.R. 4 Q.B. 127 — Frustration of contract.
11. **Pao On v Lau Yiu Long** [1980] AC 614 — Economic duress.
12. **The Universe Sentinel** [1983] 1 AC 366 — Economic duress (union blacking).
13. **Atlas Express Ltd v Kafco Importers and Distributors Ltd** (1989) 3 WLR 389 — Economic duress.
14. **Pinnel's Case** (1602) 5 Co. Rep. 117a — Part-payment rule.

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**Note**: These notes are grounded in real Commonwealth case law confirmed via free-access law databases (AustLII). All cases cited are real, though this is an abridged summary. For examination preparation, students should consult full case reports and statutory sources, particularly the statutes listed in the original exam specification (UCTA 1977, Misrepresentation Act 1967, Consumer Rights Act 2015, Sale of Goods Act 1979, etc.).