legal memory

noun Law.
  1. a period of time, now usually established by statute, during which custom, conduct, or a state of affairs must have existed or continued in order for it to have taken on the force of law or to establish a legal right or title not otherwise provable.

Origin of legal memory

First recorded in 1760–70
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018