When a boundary line dispute arises between neighboring property owners, one claim that is commonly asserted—along with adverse possession, estoppel in pais, and a few other legal bases for boundary adjustment—is “mutual recognition and acquiescence” in a common boundary. A recent opinion from the Washington Supreme Court (Merriman v. Cokeley) has refined the standard that Washington courts will apply in determining whether a party can establish title under this doctrine.
For years, Washington courts have required that a boundary established by mutual recognition and acquiescence be “certain, well defined, and in some fashion physically designated upon the ground.” In Merriman v. Cokeley, the party suing to quiet title claimed that the agreed-upon boundary line had been marked by a couple of wooden posts and a metal stake, and vegetation that had grown along the boundary line. The Supreme Court, however, found that this was insufficient to establish a boundary by acquiescence. The Court noted that “[a] fence, a pathway, or some other object or combination of objects clearly dividing the two parcels must exist,” and that in this case “[t]he three widely spaced markers . . . set in a thicket of blackberry bushes, ivy, and weeds, did not constitute a clear and well-defined boundary.” This case provides some guidance on the showing necessary to establish title under the doctrine of mutual acquiescence, but parties to boundary disputes are still left without any “bright-line” rule about what constitutes “a clear and well-defined boundary.”