Under the Bharatiya Sakshya Adhiniyam, 2023, a person who, by his DECLARATION, act or omission, intentionally CAUSES another to believe a thing to be true and to act upon that belief, is precluded from DENYING the truth of that thing. This principle is the doctrine of:

Estoppel under the BSA (the successor to old Sections 115-117 of the Indian Evidence Act) is the rule that when one person has, by his declaration, ACT or omission, intentionally caused or permitted another to believe a thing to be true and to ACT upon that belief, neither he nor his representative shall be allowed to DENY the truth of that thing in any suit or proceeding. It prevents a party from taking contradictory positions to the prejudice of one who relied on them. Estoppel is a rule of evidence and is distinct from admission or acquiescence, and must be pleaded. It operates to uphold representation-based reliance.