what is an estoppel

Estoppel is a legal principle that prevents a person from contradicting or going back on a previous statement, action, or promise that another person has relied upon. It essentially stops someone from asserting a claim or fact that conflicts with what they previously said or agreed to, ensuring consistency and fairness in legal dealings. This principle is designed to prevent injustice caused by one party reneging on their word or changing their position in a way that harms another party. There are various types of estoppel, common forms include promissory estoppel, equitable estoppel, and collateral estoppel. For example, if someone makes a promise or representation that another person relies on to their detriment, the person who made the promise may be "estopped" from later denying it. In practical use, estoppel often appears in contracts, leases, and real estate transactions where parties are required to certify facts or terms to prevent disputes about what was originally agreed upon. An estoppel certificate or letter is a document confirming the terms and status of an agreement or lease, which binds the party providing it from later contradicting those facts. In summary, estoppel promotes fairness by holding parties to their previous statements or agreements and stopping them from unfairly changing their position to the detriment of others. It is a common legal doctrine in countries with common law systems such as the U.S., U.K., and Canada. This principle protects parties by enforcing consistency in words and actions to prevent unjust outcomes.