The book attempts to analyze the status of several Anglo-American legal doctrines referred to as equitable estoppel, promissory estoppel, and proprietary estoppel. It examines the English, American and Australian law from the 18th century onwards. The book draws analogies to legal devices detectable in continental civil law and characterized by the goal similar to that performed by various types of estoppel. Among these devices there may be listed those found in the European harmonization projects (PECL, DCFR, CESL) as well as those found in the national civil codes, and specifically such as principle of good faith and fair dealing or the prohibition on the abuse of rights. Common law jurisdictions recognize a number of specific estoppel doctrines. The latter prevent the negative effects of an inconsistent conduct of the other party and counteract the occurrence of detriment or other negative consequences (often referred to by a vague notion of ‘unconscionability’) resulting from the party’s reliance on the other party’s inconsistent conduct. Estoppels are used today as ‘safety valves’ in almost all fields of Anglo-American private law. The courts apply them to settle accounts for the expenditures made on someone else’s property and also to protect the addressees of formally defective promises (made in breach of the statute of frauds) as well as to protect the parties to the negotiations that did not lead to the contract’s conclusion. Estoppels can also be found in family-law relations as a device to settle the accounts of former cohabitants or to modify the partition of the deceased’s estate. Despite the broad scope of its application, the law on estoppels is far from being settled. Significant differences occur in its interpretation under various jurisdictions. While in English law the promissory estoppel might be used only as a defence (‘a shield’), the American and Australian law recognize it as an independent cause of action (‘a sword’). There are many controversies and disputes that are currently taking place both in the courts and in the scholarship. They lead to legal uncertainty and unpredictability of decisions. The book attempts to discuss these issues and sometimes point to potential solutions.
Jan Halberda, Estoppel w angloamerykańskim prawie prywatnym (wprowadzenie) / Estoppel in Anglo-American Private Law, Księgarnia Akademicka, October 2020.