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Promissory estoppel, Detrimental reliance, Reliance damages, Expectancy damages




Professor Hillman presents evidence that contradicts several assumptions about how courts apply the doctrine of promissory estoppel. Although theorists have claimed the importance, even dominance, of the theory as a ground for enforcing promises, he shows that this theory is remarkably unsuccessful in the courts. Professor Hillman also demonstrates the crucial role of reliance in both successful and unsuccessful promissory estoppel cases, despite the "new consensus" that courts enforce promises without a showing of reliance. Finally, Professor Hillman shows that courts award damages flexibly in successful promissory estoppel cases, although analysts have claimed that courts strongly favor expectancy damages.

Professor Hillman derives his evidence from a data pool of all of the reported decisions in the United States for a two-year period in the mid-1990s in which a promissory estoppel claim either succeeded or failed or in which a court discussed promissory estoppel. He reports the results of a systematic survey of these cases. He also analyzes and discusses a representative sample of the cases in greater depth. In addition, Professor Hillman reexamines some of the cases in earlier studies that led others to report incorrectly the unimportance of reliance.

Professor Hillman also discusses why promissory estoppel has been so unsuccessful in the courts. He surmises that claimants may have overestimated the chances of success because of their failure to comprehend a judicial souring on the theory. Another possible explanation is that claimants often bring weak secondary claims of promissory estoppel. Professor Hillman leaves for another day the question of whether promissory estoppel should be more successful and whether promissory estoppel should require reliance.

Publication Citation

Published in: Columbia Law Review, vol. 98, no. 3 (April 1998).

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