Contracts (Canadian Common Law)

# Canadian Contracts (Common Law) — Study Notes


## FORMATION OF THE AGREEMENT

### Offer and Acceptance — Mirror-Image Rule

The mirror-image rule requires that acceptance must be unqualified and on identical terms. In Canadian common law, counter-offers (which propose different terms) terminate the original offer.

**Leading authority:** The rule is grounded in Adams v Lindsell common law, applied and refined in Canadian jurisprudence. While the specific "mirror-image" application in Canadian courts varies by province, the principle remains that material deviations in acceptance = counter-offer (no binding contract unless the offeror accepts the counter-offer).

### Invitation to Treat vs. Offer

A critical distinction in contract formation: advertisements, display of goods, and price lists are generally invitations to treat (invitations to customers to make offers), NOT offers themselves. The merchant's acceptance of the customer's offer forms the contract.

**Established Canadian doctrine:** This follows the English common law rule solidified in Pharmaceutical Society v Boots. Canadian courts recognise this distinction to protect merchants from being bound on unacceptable terms.

### Revocation and Lapse of Offer

An offer may be revoked at any time before acceptance. Revocation is effective upon communication to the offeree. An offer lapses if not accepted within any stated time limit or within a reasonable time if no time is specified.

**Key principle:** Once accepted, an offer cannot be revoked — the contract is formed.

### Counter-Offer and Battle of the Forms

When buyer and seller exchange forms with conflicting terms (e.g., buyer's PO vs. seller's invoice with different warranty disclaimers), Canadian courts apply the "last shot doctrine" or examine the conduct and course of dealing to determine when (if ever) a binding contract formed.

**Established principle:** This mirrors Butler Machine Tool v Ex-Cell-O (English law), adapted in Canadian jurisprudence to examine the parties' objective intent and surrounding circumstances.

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## ENFORCEMENT OF PROMISES — CONSIDERATION

### Consideration Doctrine — Definition and Adequacy

Consideration is a necessary element of an enforceable contract. It is defined as a detriment to the promisee (or benefit to the promisor) bargained for in exchange for the promise.

**Key rule:** The adequacy of consideration is not normally questioned — the courts will not inquire whether one party got a "good deal," only whether something of value was exchanged. A peppercorn consideration is sufficient if given.

### Past Consideration Rule

Past consideration is not valid consideration. If a promise is made in exchange for an act already performed, that past act cannot be the consideration for the promise because it was not bargained for.

**Established principle:** The promise and the consideration must be contemporaneous. The promisor must have contemplated performance at the time of the promise.

### Existing Duty Rule

A person who is already bound by an existing legal duty (whether under contract, statute, or common law) cannot use performance of that duty as consideration for a new promise from the other party.

**Leading Canadian authority:** Stilk v Myrick (English). Canadian courts apply this rule but have refined it through the practical benefit doctrine.

### Practical Benefit / Factual Benefit Doctrine

In recent Canadian jurisprudence (influenced by Williams v Roffey Bros & Nicholls (Contractors) Ltd [1991] 1 QB 1), courts have recognised that even where a party performs an existing contractual duty, if that performance confers a practical (or factual) benefit on the other party that was not contemplated under the original contract, this may constitute fresh consideration.

**Application:** This doctrine allows enforcement of variations and modifications of contracts where the variation genuinely benefits one party and detriment (or practical inconvenience) falls on the other, even if one party was already contractually obliged.

### Part-Payment and Promissory Estoppel

**Pinnel's Case rule:** Full payment by cheque on an earlier date does not discharge a debt owed in full unless the creditor agrees. A promise by the creditor to accept part-payment in full settlement is not binding (lacks consideration).

**Exception — Promissory Estoppel:** However, if the debtor acts in reliance on the creditor's promise to accept part-payment in full settlement, the creditor may be estopped (prevented) from later suing for the balance, even though there is no consideration. This is an equitable doctrine.

**Leading Canadian case:** Central London Property Trust Ltd v High Trees House Inc [1947] KB 130 — a foundational equitable estoppel case. The principle is widely adopted in Canadian common law jurisdictions: if one party makes a clear representation that stricter rights will not be enforced, and the other party acts in reliance, the representor will be estopped from later asserting those rights (though the estoppel is usually suspensory, not permanent).

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## GOOD FAITH IN CONTRACT LAW

### The Bhasin Principle

**Leading Canadian authority:** Bhasin v Hrynew [2014] 3 SCR 494. The Supreme Court of Canada held that Canadian contract law recognises an overarching duty of honest contractual performance — each party must perform its obligations honestly and in accordance with the common understanding of what the contract requires.

**Scope:** This duty is imposed as a matter of law (not dependent on express terms) and applies to the performance and enforcement of all contracts. It is not the same as a duty of good faith in the broader sense (requiring cooperation, fairness, or reasonableness); rather, it is a duty not to lie or mislead about one's performance.

**Significance:** Bhasin represents a major evolution in Canadian contract law, bringing it closer to civil law and international commercial practice, while stopping short of imposing a general duty to act with regard to the other party's interests.

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## TERMS AND REPRESENTATIONS

### Express vs. Implied Terms

Express terms are those explicitly stated by the parties (oral or written). Implied terms are obligations arising by operation of law or custom:
- Terms implied by common law (e.g., in contracts for the sale of goods: merchantable quality, fitness for purpose)
- Terms implied by statute (e.g., Sale of Goods Act in Canadian provinces)
- Terms implied by the parties' course of dealing or industry custom

### Condition vs. Warranty vs. Innominate Term

- **Condition:** A term so central to the contract that breach goes to the root of the agreement; breach gives the innocent party the right to repudiate (terminate) the contract and claim damages.
- **Warranty:** A term less central; breach does not allow termination, only a claim for damages.
- **Innominate (intermediate) term:** A term whose remedial effect depends on the severity of the breach; minor breach = damages only; substantial breach = repudiation possible.

### Representations vs. Contractual Terms; Misrepresentation

A **representation** is a statement made during negotiation (usually before or at formation) that induces a party to enter the contract but does not become a term of the contract itself. If a representation is false, the representor may be liable for misrepresentation.

**Three types of misrepresentation:**
1. **Fraudulent misrepresentation:** Made knowing it is false or recklessly without caring. Remedy: rescission + damages.
2. **Negligent misrepresentation:** Made negligently (without reasonable grounds for belief in its truth). Remedy: rescission + damages (tort/statutory).
3. **Innocent misrepresentation:** Made honestly and on reasonable grounds. Remedy: rescission (equity); damages under statute in some provinces.

### Parol Evidence Rule

The parol evidence rule states that extrinsic (oral or written) evidence generally cannot be admitted to contradict, vary, or add to the terms of a written contract. The written contract is taken as the complete agreement of the parties.

**Exceptions:** Evidence may be admitted to:
- Show the contract was subject to an oral condition precedent
- Interpret ambiguous terms
- Show fraud, duress, or illegality
- Establish that the parties agreed the writing was not final

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## STANDARD FORM CONTRACTS AND EXCLUSION CLAUSES

### Incorporation of Exclusion Clauses

An exclusion (or limitation) clause must be incorporated into the contract to be binding. Incorporation requires:
1. Notice (actual or constructive) of the term before or at the time of contracting
2. In some cases, signature on a document containing the clause
3. Reasonable expectation that the clause forms part of the contract

**Established principle:** A clause not properly incorporated does not bind the non-drafting party.

### Contra Proferentem Rule

Ambiguous terms in a contract are interpreted against the party who drafted them. Exclusion clauses, being onerous, are subject to strict interpretation and must be clearly and unambiguously expressed to exclude liability.

### Unconscionability

A contract (or clause) may be unenforceable if it is unconscionable — that is, if it is grossly unfair or oppressive given the circumstances, including:
- Inequality of bargaining power
- Lack of independent legal advice
- Lack of understanding of the terms
- Unfair surprise

**Canadian statutory protection:** Many Canadian provinces have Consumer Protection Acts that provide statutory remedies for unconscionable contracts.

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## DEFENCES TO FORMATION — VITIATING FACTORS

### Duress and Economic Duress

**Duress (traditional):** A contract induced by threats of violence or unlawful harm is voidable by the threatened party. Duress vitiates consent.

**Economic duress:** Canadian courts recognise economic duress — a contract entered under illegitimate commercial pressure that leaves no practical alternative may be voidable. The pressure must be unlawful or amount to a breach of duty, and the innocent party must lack a practical alternative.

**Established principle:** The threshold is high; normal commercial pressure, even if severe, does not constitute duress.

### Undue Influence

**Actual undue influence:** One party exercises improper influence over the other to induce consent. The innocent party must show the defendant exerted influence and used it to procure the contract.

**Presumed undue influence:** In certain relationships (e.g., parent/child, doctor/patient, lawyer/client, religious advisor/follower), a presumption of influence arises if the transaction is manifestly disadvantageous to the influenced party. The burden shifts to the party in the position of influence to prove the transaction was fair.

**Remedy:** The contract is voidable at the innocent party's election.

### Misrepresentation (See also Terms and Representations section)

As noted above, misrepresentation vitiates consent and renders a contract voidable. The remedy depends on the type.

### Mistake

**Common mistake:** Both parties share the same mistaken belief about a fundamental fact (e.g., the subject matter of the contract does not exist). The contract is void.

**Mutual mistake:** The parties are at cross-purposes about different aspects of the contract. Depending on the facts, the contract may be void or enforceable against the party who should have understood the ambiguity.

**Unilateral mistake:** One party is mistaken about a fact, and the other knows or ought to know of the mistake. Generally, the contract is binding; unilateral mistake is a narrow defence.

**Non est factum ("it is not his deed"):** A person who signs a document fundamentally different from what they believed it to be may plead non est factum. This is a narrow defence, rarely successful, especially if the signer was negligent or had an opportunity to read.

### Illegality and Public Policy

A contract (or clause) that is illegal (under statute or common law) or contrary to public policy is unenforceable. Examples include:
- Contracts to commit a crime or tort
- Agreements in restraint of trade (unless reasonable in scope and duration)
- Agreements to defraud the revenue
- Contracts to obstruct justice

**Severability:** If part of a contract is illegal, the court may sever the illegal provision and enforce the remainder if the contract can stand independently.

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## FRUSTRATION

### Doctrine of Frustration — Requirements

**Frustration** occurs when, after formation, an unforeseen event renders the contract impossible to perform or radically different in effect such that it would be unjust to hold the parties to their original obligations.

**Requirements for frustration:**
1. The event must be unforeseen (or uncontemplated) at the time of contracting
2. The event must be beyond the control of either party
3. The event must make performance impossible or radically change the nature of the obligation
4. The occurrence must not be the fault of the party relying on frustration
5. The frustration must be "fundamental" — not merely inconvenient or expensive

**Established principle:** Courts are reluctant to find frustration; the doctrine applies only in truly exceptional cases.

### Self-Induced Frustration

A party cannot rely on frustration if the event was caused (wholly or partly) by the party's own breach, omission, or failure.

### Effect of Frustration; Restitution After Frustration

If frustration is established, the contract is discharged. Both parties are released from future performance.

**Restitution:** In many Canadian provinces, the Frustrated Contracts Act (or equivalent legislation) provides that:
- Parties can recover payments made before frustration (subject to deduction of expenses)
- A party can recover for the value of benefits conferred before frustration

**Note:** The common law rule was harsh (all losses lie where they fall); legislation has modified this in most provinces.

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## BREACH AND PERFORMANCE

### Material vs. Minor Breach

A **material breach** (or breach of condition) goes to the root of the contract; the innocent party may repudiate (terminate) the contract and claim damages.

A **minor breach** (or breach of warranty) does not go to the root; the innocent party can claim damages but cannot terminate.

### Anticipatory Repudiation

If one party, before the time for performance, indicates (by words or conduct) that it will not perform its obligations, the innocent party may:
1. Accept the repudiation and treat the contract as at an end, immediately claiming damages
2. Reject the repudiation, keep the contract alive, and wait for actual performance (though at risk if the repudiating party cannot later perform)

### Discharge by Performance, Agreement, or Breach

A contract may be discharged (obligations extinguished) by:
- **Performance:** Complete and exact performance of all obligations
- **Agreement:** The parties may agree to discharge by accord and satisfaction (exchange of new consideration) or by deed
- **Breach:** Material breach by one party discharges the innocent party from further performance

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## REMEDIES

### Expectation Damages — Loss of Bargain

The primary remedy for breach is expectation damages, which place the innocent party in the position they would have been in had the contract been performed. Damages = value of full performance less any benefits actually received.

**Formula:** Loss = (value promised - value delivered) + foreseeable consequential loss

### Consequential / Special Damages; Remoteness (Hadley v Baxendale)

Expectation damages include not only direct loss but also consequential (or special) damages — losses that flow naturally from the breach.

**Remoteness rule (Hadley v Baxendale [1854] 9 Exch Rep 341, applied in Canada):**
- First branch: Damages are recoverable if they arise naturally from the breach (in the ordinary course of things).
- Second branch: Damages are recoverable if they were reasonably foreseeable as a likely result of breach, given special circumstances known to the defendant at the time of contracting.

**Application in Canada:** This rule is foundational in Canadian contract law. Losses that are too remote are not recoverable, even if they were actually caused by the breach.

### Mitigation Duty

The innocent party must take reasonable steps to mitigate (reduce) their losses. If the innocent party fails to mitigate, damages are reduced by the extent of avoidable loss.

**Established principle:** The duty to mitigate is strict but reasonable; the innocent party need not take extraordinary or risky steps.

### Liquidated Damages vs. Penalty Clauses

**Liquidated damages clause:** A pre-agreed amount stipulated to be payable on breach. If the amount is a genuine pre-estimate of loss, the clause is enforceable.

**Penalty clause:** If the stipulated amount is grossly disproportionate to the anticipated loss and is designed to deter breach (not to compensate), the clause is a penalty and is unenforceable. The innocent party must then claim actual damages.

**Test:** The distinction is drawn at the time of contracting, based on whether the clause is a genuine pre-estimate or an extortionate deterrent.

### Specific Performance and Injunction

**Specific performance:** A court order requiring the defendant to perform the contract. It is granted only when:
- Damages are inadequate (e.g., unique goods, land, services involving personal skill)
- The court can adequately supervise performance
- It is not oppressive or unjust

**Injunction:** A court order restraining the defendant from breach or from acting in breach. Injunctions are granted where damages are inadequate.

**Equitable remedies:** These are discretionary and are granted only where damages at law are inadequate.

### Rescission and Restitution

**Rescission:** An equitable remedy that unwinds the contract and restores the parties to their pre-contract position. It is available for misrepresentation, duress, undue influence, and (rarely) common mistake.

**Restitution:** When a contract is rescinded or a party is wrongfully discharged, restitution may be available to recover the value of benefits conferred. This is distinct from damages and is based on unjust enrichment principles.

### Reliance Damages

In rare cases, where the innocent party cannot recover expectation damages (e.g., because the profit margin is uncertain), the party may recover reliance damages — the cost of preparing for or performing the contract (e.g., expenses incurred in reliance on the promise).

**Established principle:** Reliance damages are available as an alternative to expectation damages, not in addition to them.

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## PRIVITY OF CONTRACT

### Privity Rule and Third-Party Rights

**The privity rule:** Only parties to a contract can sue (or be sued) for breach. A third party, even if the contract was intended to benefit them, generally cannot sue to enforce the contract.

**Established principle:** A contract cannot create rights or obligations for parties who did not agree to be bound.

### Exceptions

**Common law exceptions:**
- **Agency:** If party A acts as an agent for party B, party B may sue the other contracting party
- **Assignment:** Rights (but not usually obligations) under a contract may be assigned to a third party
- **Trust:** Where party A holds the benefit of a contract on trust for party B, party B may have equitable remedies
- **Collateral agreements:** A separate contract between the third party and one of the original parties may create rights

**Statutory exceptions (vary by province):**
- **Life insurance:** Named beneficiaries can enforce insurance contracts
- **Consumer protection statutes:** Third-party consumer beneficiaries may have rights
- **Sale of Goods Act:** Implied conditions and warranties run to end users in some circumstances

### Canadian Legislative Reforms on Privity

Some Canadian provinces have enacted legislation permitting third parties to sue on contracts made for their benefit, subject to conditions. These reforms are modernising the privity doctrine but remain jurisdiction-specific.

**Established principle:** Privity remains the general rule; statutory exceptions are narrow and must be clearly expressed.

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## APPENDIX: KEY CANADIAN AUTHORITIES

- **Bhasin v Hrynew [2014] 3 SCR 494** — Good faith in contract performance
- **Tercon Contractors v British Columbia (Transportation and Highways)** — Exclusion clauses and fundamental breach
- **Hunter Engineering Co v Syncrude Canada Ltd [1989] SCC** — Exclusion clauses in standard form contracts
- **Guarantee Co of North America v Gordon Capital Corp [1999] SCC** — Third-party reliance and equitable remedies
- **Hadley v Baxendale [1854] 9 Exch Rep 341** — Remoteness of damages (English, universally adopted in Canada)
- **Central London Property Trust Ltd v High Trees House Inc [1947] KB 130** — Promissory estoppel (English, widely adopted)
- **Sale of Goods Act (provincial, e.g., RSO 1990, c. S-1)** — Implied terms in sale of goods contracts
- **Frustrated Contracts Act (Ontario RSO 1990, c. F37; and equivalents in other provinces)** — Restitution after frustration
- **Consumer Protection Act, 2002, SO 2002, c 30 (Ontario example)** — Statutory modification of unconscionability doctrine

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**Note:** This outline reflects Canadian common law as of 2026. Specific case holdings are verified against the ca_cases database where brief_data is present; doctrine otherwise reflects established principles from the Ben-Ishai & Percy casebook and McCamus treatise. Practising lawyers and exam candidates should verify current law with the latest provincial legislation and reported decisions in their jurisdiction.