Promissory Estoppel and Estoppel by Representation Compared: Statements of Fact, Promises of Future Conduct and the Public Law Dimension

Estoppel by representation is a rule of evidence. Where a person has by his declaration, act or omission caused another to believe a thing to be true and to act on that belief, neither he nor his representative is allowed to deny the truth of it in any proceeding between them. It operates on statements of existing fact and prevents a party from asserting the contrary. Promissory estoppel is different in almost every respect. It operates on promises about future conduct, it belongs to equity rather than to evidence, and in India it has become a source of substantive obligation enforceable against the State. This topic compares the two and explains why the differences matter in administrative law.

1. Estoppel by Representation

The rule of evidence

The general rule is that where one person has, by his declaration, act or omission, intentionally caused or permitted another person to believe a thing to be true and to act upon such belief, neither he nor his representative shall be allowed, in any suit or proceeding between himself and such person or his representative, to deny the truth of that thing. The rule operates on a representation of existing fact, requires that the representation was intended to be acted upon and was in fact acted upon, and binds only as between the parties to the proceeding. Related provisions preclude a tenant from denying the landlord's title during the tenancy, and preclude a licensee of property from denying the licensor's title at the time the licence was given.

2. The Comparison

Basis	Estoppel by representation	Promissory estoppel
Nature	A rule of evidence	A rule of equity, and in India a source of obligation
Subject of the statement	An existing fact	Future conduct; a promise
What it prevents	Denying the truth of the fact represented	Resiling from the promise made
Requires action on the faith of it	Yes	Yes
Requires detriment	Not strictly; the change of position suffices	A change of position; detriment in the strict sense not essential
Sword or shield	A shield; it does not found a cause of action	In India it may found a claim against the State
Pre-existing legal relationship	Not required	Not required in India; required in the classical English formulation
Effect	The fact is taken as represented	The promise is enforced, subject to equity
Against the Government	Available, subject to the limits below	Available in executive functions
Public interest defence	Limited	Available, but only on material
Against a statute	Not available	Not available

3. Promissory Estoppel as a Source of Obligation

📖 Century Spinning and Manufacturing Co. Ltd. v. Ulhasnagar Municipal Council, (1970) 1 SCC 582

Facts: A municipal authority represented to industrial units in an area that they would be exempt from octroi duty for a period if they set up their establishments there, and the units proceeded on that footing. The authority subsequently sought to levy the duty. The units moved the High Court under Article 226, which declined to entertain the petition on the footing that a claim founded on a representation of this kind raised contractual questions unsuitable for the writ jurisdiction.

Held: The Supreme Court held that the High Court was not justified in dismissing the petition on that ground and remitted it. It held that a public body is not exempt from liability to carry out its representation merely because the obligation is not recorded in a formal contract, and that if a party acting on a representation made by a public body alters his position, he is entitled to enforce the representation against it even though it is not in the form of a contract. The Court held that the writ jurisdiction is available for such a claim and that a petition ought not to be rejected merely because it involves a claim arising out of a representation; whether relief should be granted depends on the facts, but the High Court cannot decline to examine the matter on the ground that it lies outside Article 226.

Ratio: A public body is bound by a representation on which a party has altered his position, even though it is not embodied in a formal contract, and such a claim may be enforced under Article 226.

4. What Must Be Established

📖 Delhi Cloth and General Mills Ltd. v. Union of India, (1988) 1 SCC 86

Facts: A claim was founded on promissory estoppel against the Government in relation to the levy of duty, and the question arose what a party invoking the doctrine must plead and establish, and what material the Government must produce if it seeks to resile.

Held: The Supreme Court set out the requirements. It held that a party invoking promissory estoppel must plead and prove a clear and unambiguous promise, that the promise was intended to affect the legal relationship of the parties and to be acted upon, that he altered his position by acting on the promise, and that it would be inequitable to permit the promisor to resile. The Court held that the doctrine does not arise from a vague or general statement, and that the party must establish the precise representation relied on and the manner in which he acted on it; conversely, where these ingredients are established, the burden shifts to the Government, which must place material before the court showing that the public interest requires that it be permitted to go back on the promise, a bare assertion being insufficient. The Court reiterated that no estoppel operates against a statute or against the exercise of legislative power.

Ratio: The party invoking promissory estoppel must plead and prove a clear promise, an intention that it be acted upon, an alteration of position, and inequity in resiling; the Government must then place material justifying any departure.

5. The Common Limits against the State

No estoppel against a statute. Neither doctrine can compel an authority to act contrary to law or to grant what the statute forbids.
No estoppel against legislative power, so neither prevents the making, amendment or repeal of a law or of rules.
No estoppel on a question of law, so a concession or a mistaken view of law binds neither party.
No estoppel where the officer lacked authority to make the representation or the promise.
No estoppel to circumvent Article 299, since the constitutional form of a government contract cannot be supplied by representation.
Overriding public interest may relieve the State, but only on material placed before the court.

6. Why the Distinction Matters

Question	Estoppel by representation	Promissory estoppel
Can it found a claim?	No; it prevents a denial	Yes, against the State in India
Does it apply to a statement about the future?	No; only to existing fact	Yes; that is its whole field
Can it be raised in a writ petition?	As an evidentiary bar	As the foundation of the claim (Century Spinning)
What must be pleaded?	The representation of fact and the action on it	The promise, the intention, the alteration of position and the inequity
What defeats it?	Proof that the representation was not made or not relied on	Material showing overriding public interest (Delhi Cloth)
Is a pre-existing relationship required?	No	No, in India

⚠ The Indian departure is that the promise founds the claim

In the classical English formulation, promissory estoppel operates only as a shield: it qualifies the enforcement of existing rights and does not create a cause of action, so a promisee cannot sue upon the promise alone. Indian law departed from that in the government cases, and the departure is what gives the doctrine its importance in this subject. A person who acted on a government assurance is not confined to raising it in defence when the State sues him; he may move the High Court under Article 226 and found his claim on the promise, and the State must then justify any departure with material. Estoppel by representation remains what it always was, a rule of evidence barring a denial, and it cannot be used in that way.

7. The Position in Summary

Estoppel by representation is a rule of evidence operating on statements of existing fact and preventing a denial; promissory estoppel is equitable, operates on promises of future conduct and enforces the promise.
A public body is bound by a representation on which a party has altered his position, even without a formal contract, and such a claim may be enforced under Article 226 (Century Spinning).
The party must plead and prove a clear promise, an intention that it be acted upon, an alteration of position and inequity in resiling, after which the Government must place material justifying departure (Delhi Cloth and General Mills).
Neither doctrine operates against a statute, against legislative power, on a question of law, where the officer lacked authority, or to circumvent Article 299.
The Indian departure from the English position is that promissory estoppel may found a claim against the State rather than operating only as a shield.

8. Related Topics and Provisions

Doctrine of Promissory Estoppel (Topic 172) and Promissory Estoppel against the Government (Topic 55).
Legitimate Expectation vs Promissory Estoppel (Topic 203).
Government Contracts and Public Tenders (Topic 138): Article 299 and the limits of estoppel.
Fettering of Discretion (Topic 184): why an authority cannot contract away a statutory power.
Power to Exempt under Delegated Legislation (Topic 36): withdrawal of exemptions.
Constitution of India: Articles 14, 226, 265 and 299; Indian Evidence law on estoppel.