Acquiescence

In law, acquiescence occurs when a person knowingly stands by without raising any objection to the infringement of their rights, while someone else unknowingly and without malice aforethought makes a claim on their rights. Consequently, the person whose rights are infringed loses the ability to make a claim against the infringer, or succeed in an injunction suit due to the infringer's conduct. The term is most generally a kind of "permission" given by silence or passiveness.

The common law doctrine of estoppel by acquiescence is applied when one party gives legal notice to a second party of a fact or claim, and the second party fails to challenge or refute that claim within a reasonable time. The second party is said to have acquiesced to the claim, and is estopped from later challenging it, or making a counterclaim. The doctrine is different from estoppel by laches to the extent that a lache may be involuntary but acquiescence involves an intentional act of the party who is accused of aquiescence.

This occurred in the second Georgia v. South Carolina case before the U.S. Supreme Court in 1990, when it was ruled that Georgia could no longer make any claim to an island in the Savannah River, despite the 1787 Treaty of Beaufort's assignment to the contrary. The court said that the state had knowingly allowed South Carolina to join the island as a peninsula to its own coast by dumping sand from dredging, and to then levy property taxes on it for decades. Georgia thereby lost the island-turned-peninsula by its own acquiescence, even though the treaty had given it all of the islands in the river (see adverse possession).

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