Beck v. Neville: Establishing a New Boundary Dispute Doctrine in Arizona

By Aliza Lewis. 

In January 2024, the Arizona Supreme Court issued a landmark decision in Beck v. Neville, officially establishing a legal doctrine for resolving boundary disputes between adjacent property owners. The court’s resolution not only settled the specific dispute between neighbors but also formally recognized the doctrine of “boundary by acquiescence” in Arizona law, providing a new avenue for resolving similar property conflicts in the future.

Fences Make Good Neighbors: Arizona Embraces Boundary by Acquiescence

Beck v. Neville originated with neighbors, the Becks and the Nevilles, who purchased their property around the same time in 1998-2000. After some yard renovations, the Becks’ landscapers mistakenly set decorative stamped concrete paver bricks short of the property line, creating the 135-square-foot triangle-shaped area in dispute. Years later, the Becks wanted to do more remodeling, which required digging up the disputed property. When they notified the Nevilles of their planned construction, the Nevilles claimed they owned the triangle of property due to adverse possession and boundary by acquiescence. The legal question was whether Arizona has affirmatively acknowledged the doctrine of boundary by acquiescence and what burden of proof is required to prove such a claim.

In a unanimous opinion authored by Justice Montgomery, the Arizona Supreme Court held that the boundary by acquiescence doctrine had been a part of Arizona jurisprudence for decades but took this as a chance to clarify the elements of the doctrine. Previously, in Mealey v. Arndt, the Arizona Court of Appeals looked to other jurisdictions to set out elements for this claim. The elements for a boundary by acquiescence claim in Arizona are “(1) occupation or possession of property up to a clearly defined line; (2) mutual acquiescence by the adjoining landowners in that line as the dividing line between their properties; (3) continued acquiescence for ten years; and, . . . (4) uncertainty or dispute as to the true boundary.” The Arizona Supreme Court added the fourth element, taking the other three from the Court of Appeals opinion. Additionally, the party asserting the claim bears the burden of proof for each element, which must be proven with clear and convincing evidence.

The court deeply analyzed the significance of property rights in Arizona, citing the Virginia Declaration of Rights, the Declaration of Independence, and federal constitutional jurisprudence. Vice Chief Justice Timmer expressed concern about including paragraphs citing the Constitution in a noteworthy concurrence. She worried a citation to the federal Constitution may affect how state constitutional rights are interpreted and applied in the future. This concern stems from the fact that the individual property rights under the Constitution were not issues directly addressed in the current case, which means interested parties did not have the opportunity to provide input on this potentially far-reaching matter.

After clarifying the elements of boundary by acquiescence, the Arizona Supreme Court applied the facts. The Court held that the Nevilles’ claim failed as a matter of law. Three of the four elements were not met—there was no proof of an uncertain or disputed boundary, no continuous occupation up to a defined line, and no mutual agreement that the pavers were the new boundary. The only element met was the continued acquiescence for a sufficient period of time, which is ten years in Arizona.

This case serves as an important precedent for boundary by acquiescence used in boundary disputes in Arizona. It sets clear standards for lawyers to follow, clarifies how boundary by acquiescence differs from adverse possession, and increases the importance of property surveys. 

Boundary Lines & Legal Landscapes

The doctrine adopted by Arizona is similar to versions adopted by other Western states. In Beck v. Neville, the Arizona Supreme Court heavily relied on Utah cases when establishing the boundary by acquiescence doctrine. A few doctrines throughout the Western United States maintain similar elements to deal with boundary disputes. For example, the “agreed boundary line” doctrine is used in Montana to resolve boundary line disagreements. While elements of the agreed boundary line and boundary by acquiescence vary in wording, they have the same application. In both Arizona and Montana, (1) the location of the true boundary is disputed, (2) the parties must agree on the boundary, (3) actions showing possession and occupation up to the agreed boundary line are required, and (4) a specific time period must be met.

On the other hand, Utah has adopted both the agreed boundary line and the boundary by acquiescence doctrines to handle boundary disputes. However, Utah has created a clear separation between the doctrines by removing the time requirement for an agreed upon boundary line. Overall, this reinforces the idea that the doctrines are more similar than different, even though Utah added an alteration to further separate the two.

The level of analysis necessary for boundary disputes depends on how many elements each state has chosen. In Idaho and Colorado, only two elements need to be met for a boundary modification with adjacent properties. In these states, the level of analysis is minimal compared to the deep dive into neighbor behavior needed for Arizona’s version of boundary by acquiescence. Ultimately, Western states with rural areas where land boundaries are often unclear or undefined have adopted a version of boundary by acquiescence to solve boundary disagreements.

Beck Moving Forward 

This peculiar cause of action is officially in Arizona jurisprudence, with guidance for lawyers and judges applying boundary by acquiescence moving forward. The Court’s decision in Beck demonstrates their commitment to upholding property rights while also recognizing the need for flexibility in certain circumstances. Further, this decision was needed to advance Arizona jurisprudence to match other Western states’ property law boundary doctrines throughout the United States.