Arizona Supreme Court Recognizes the Doctrine of Boundary By Acquiescence

Beck v. Neville, No. CV-22-0134-PR, Supreme Court of Arizona, January 9, 2024

This property dispute between neighbors Beck and Neville presented the Arizona Supreme Court the opportunity to formally recognize boundary by acquiescence under Arizona state law and define the contours of this doctrine. The case involved a small triangular parcel of land totaling 135 square feet near the property line between the neighbors’ adjoining lots. In 1998 and 2000, Beck and Neville purchased adjoining properties respectively. The properties sit at slightly different elevations, with the Beck property uphill from the Neville property.

In 2004, the Becks undertook some landscaping upgrades to their front yard which included installing decorative concrete paver bricks to prevent colored rocks from flowing downhill onto the Neville property. However, the landscapers mistakenly set the concrete pavers about 10 feet within the Becks' actual recorded property line instead of along the boundary. This created the appearance that the pavers lined a gravel driveway leading from the street back to the Neville property's front gate.

When the Becks learned of the landscapers' mistake, they notified the Nevilles but did not have the paver bricks relocated. The Nevilles claimed the Becks later removed and replaced the pavers in the same incorrect location in 2014, but the Becks denied making any changes. There were occasional disputes over the years when the Nevilles would not allow the Becks to park vehicles in the gravel driveway area, but no explicit assertions by the Nevilles of owning the disputed 135 square foot triangle,

This changed in 2019 when drainage work on the Beck property required digging up the area with the paver bricks, which the Becks planned to relocate to the recorded property line. The Nevilles then sent the Becks a cease-and-desist letter claiming ownership of the disputed land by adverse possession and boundary by acquiescence.

The Becks filed an action to quiet title. The trial court granted them summary judgment after finding insufficient evidence supported the Nevilles' claims. On appeal, the court of appeals reversed in a split decision and remanded for further proceedings.

The question of boundary by acquiescence had arisen in a few prior Arizona cases, with the landmark case of Mealey v. Arndt (2003) outlining some elements of the claim but never formally adopting the doctrine. Finding the issue squarely presented on appeal, the Arizona Supreme Court officially recognized the doctrine of boundary by acquiescence, under which neighboring landowners may mutually recognize and acquiesce to a boundary line over an extended period of time, even if it diverges from the legal property line. The Court reasoned that the doctrine serves policy goals of avoiding litigation and promoting stability of land ownership.

In outlining the required elements for a boundary by acquiescence claim, the Court closely followed the standards discussed in the Mealey v. Arndt case. This includes the claimant proving by clear and convincing evidence: (1) occupation or possession of land up to a clearly defined line; (2) mutual acquiescence between neighbors that the line represents the accepted boundary between properties; and (3) continued acquiescence for the statutory period (10 years in Arizona).

However, the Court added an additional element not explicitly included in Mealey – the requirement to prove uncertainty or dispute as to the true, legal boundary line at the time of acquiescence. The Court explains that without uncertainty, there would be no need for neighbors to accept a different boundary line. Requiring proof of uncertainty protects against unwitting property transfers and unnecessary disputes over boundaries that could be definitively ascertained from deeds, surveys or other records.

The Court justified the clear and convincing evidence standard by underscoring the unique importance of private property rights, tracing back principles valuing such rights to the Declaration of Independence. An interest as significant as one's own land, the Court reasoned, demands a higher standard of proof before ownership may be involuntarily altered.

Applying this new four-prong test for boundary by acquiescence to the facts of the case presented, the Court hedl that the Nevilles’ claim failed as a matter of law. Critically, the Nevilles provided no evidence of uncertainty over the recorded boundary line, which was clearly documented in deeds and surveys.

The evidence also did not sufficiently establish the elements of occupation and mutual acquiescence over the alternate boundary marked by the concrete pavers installed by the Becks in 2004. The Court reasoned that occasionally parking on a disputed area did not constitute actual possession and appropriation of the land, but merely casual use. And despite installing the pavers, the Becks did not demonstrate acceptance of a new property line, thus failing the mutual acquiescence test.

By formally adopting boundary by acquiescence and clarifying its elements, the Arizona Supreme Court provides important guidance to lower courts and property owners going forward. Requiring proof of uncertainty protects legal property lines, while respecting the informal arrangements neighbors may reasonably make through long-acquiesced use. The Court rightly sets a high bar through a heightened evidentiary standard, given the significance of altering legal property rights.