A principle or rule of law derived from judicial decisions, statutes, or longstanding custom that guides the resolution of legal disputes.
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Cases
Uniform Acts
How its tested
Common Examples
6
Merger of Inchoate Offense
Luis Lopez agreed with another to commit arson and later set the fire himself. The completed felony absorbed the preliminary agreement under the governing rule, so prosecutors charged only the arson and treated the earlier steps as subsumed.
Risk Passes at Contract
Lucas Lee signed a binding contract to buy a warehouse from Lighthouse Shipping. Before closing a storm destroyed the roof. Equity treated Lucas as owner from the moment of contract formation, so he bore the loss and remained obligated to pay the full price.
Privilege Covers Employee Reports
Latoya Lane, a mid-level manager at Liberty Trust, sent a memo to in-house counsel at her supervisor's direction describing possible regulatory violations. The communication remained protected even though Lane was not part of senior management.
Lamar Lewis bought waterfront land subject to a new municipal setback ordinance. The ordinance limited building placement but did not create a servitude because public land-use rules fall outside that category.
Heirs Language Creates No Reversion
Logan Lane's will left property to his heirs at law. The language did not trigger any reversionary interest in the estate because the doctrine that once supplied such a result has been eliminated.
Agreement Alone Completes Conspiracy
Lance Lee and a colleague reached an understanding to falsify records with the required intent. The offense was complete at that moment even though no further step was taken.
3 common questions
Students Frequently Ask...
How does a legal doctrine differ from a single case holding?
A doctrine synthesizes multiple decisions or statutes into a governing principle that courts apply across fact patterns, whereas a single holding resolves only the dispute before the court.
Can a legal doctrine be abolished by statute?
Yes. A legislature may eliminate a common-law doctrine entirely, as occurred when the worthier-title rule was removed as both a rule of law and a rule of construction.
Does every legal doctrine require an overt act?
No. Some doctrines, such as common-law conspiracy, treat the agreement itself as sufficient without any further act.
5 U.S. (1 Cranch) 137 (1803)
…actions enjoined by law but that in that case the mandamus ought not to issue if the report did not confer a legal right. That doctrine is not novel now advanced. It is true the mandamus now sought is not for performance of an act expressly enjoined by statute but to deliver a commission where the acts of Congress are…