Laches (equity)

Laches (/ˈlætʃᵻz/, LA-chəz, like "latches"; /ˈleɪtʃᵻz/, LAY-chəz; Law French: "remissness", "dilatoriness", from Old French laschesse) refers to a lack of diligence and activity in making a legal claim, or moving forward with legal enforcement of a right, in particular with regard to equity; hence, it is an unreasonable delay that can be viewed as prejudicing the opposing [defending] party. When asserted in litigation, it is an equity defense, that is, a defense to a claim for an equitable remedy. The person invoking laches is asserting that an opposing party has "slept on its rights", and that, as a result of this delay, circumstances have changed, witnesses or evidence may have been lost or no longer available, etc., such that it is no longer a just resolution to grant the plaintiff's claim. Laches is associated with the maxim of equity, "Equity aids the vigilant, not the sleeping ones [that is, those who sleep on their rights]." Put another way, failure to assert one’s rights in a timely manner can result in a claim being barred by laches.

Laches is a legal term derived from the Old French laschesse, meaning "remissness" or "dilatoriness", and is viewed as the opposite of "vigilance". Per Kathryn Fort, the United State Supreme Court case 'Costello v. United States' 365 US 265, 282 (1961) is often cited for a definition of laches. Invoking laches is a reference to a lack of diligence and activity in making a legal claim, or moving forward with legal enforcement of a right, in particular with regard to equity, and so is an "unreasonable delay pursuing a right or claim... in a way that prejudices the [opposing] party". When asserted in litigation, it is an equitable defense, that is, a defense to a claim for an equitable remedy. The essential element of laches is an unreasonable delay by the plaintiff in bringing the claim; because laches is an equitable defense, it is ordinarily applied only to claims for equitable relief (such as injunctions), and not to claims for legal relief (such as damages). The person invoking laches is asserting that an opposing party has "slept on its rights", and that, as a result of this delay, witnesses and/or evidence may have been lost or no longer available, and circumstances have changed such that it is no longer just to grant the plaintiff's original claim; hence, laches is associated with the maxim of equity: Vigilantibus non dormientibus æquitas subvenit ("Equity aids the vigilant, not the sleeping ones [that is, those who sleep on their rights]"). Put another way, failure to assert one’s rights in a timely manner can result in a claim being barred by laches. Sometimes courts will also require that the party invoking the doctrine has changed its position as a result of the delay, but that requirement is more typical of the related (but more stringent) defense of estoppel.

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