9.2 Boundary by Agreement, Acquiescence & Estoppel

Why these doctrines exist

Deeds describe lines; people live along fences. Courts favor repose: a line that neighbors have treated as the boundary for many years, or have deliberately settled, is often held to be the boundary even if a modern retracement differs. Mississippi recognizes three doctrines besides adverse possession under § 15-1-13 (Section 9.1).

1. Boundary by parol agreement

Elements, as generally applied

1. Uncertainty or dispute. The true location of the common line is uncertain or genuinely disputed.
2. Agreement on a definite line. The adjoining owners agree on a specific line on the ground.
3. Execution. The agreement is carried out by possession, such as fencing, clearing, or building to the agreed line.

Statute of Frauds. Section 15-3-1 requires a signed writing for contracts for the sale of land. An agreed boundary that settles an uncertain line is treated as locating the line the existing deeds describe, not as conveying land, so it can be enforced without a deed. If both owners know where the true line is and simply agree to move it for convenience, that is a transfer of land and needs a proper written conveyance. The best practice is still to put the agreed line in writing: a recorded boundary-line agreement with a survey plat. Under § 73-13-49, attorneys may draft such agreements, but locating the new line on the ground is surveying.

2. Boundary by acquiescence

Acquiescence rests on mutual recognition over time rather than an express agreement:

• a visible, definite line, typically a fence, hedgerow, or ditch;
• that both adjoining owners treated as the boundary, each occupying up to it without objection;
• for a long period. Mississippi courts have generally used the ten-year adverse-possession period as the benchmark.

Contrast with adverse possession. Adverse possession turns on one party's hostile claim. Acquiescence turns on both parties' peaceful acceptance. A fence of convenience, built to keep cattle out of a slough without regard to the line, does not support acquiescence if the owners understood it was not the boundary.

3. Estoppel

Estoppel prevents an owner from asserting the true line when that would be unjust because of the owner's own conduct:

1. The owner represented a line as the boundary, by words, by pointing out a corner, or sometimes by silence when there was a duty to speak.
2. The neighbor relied on it in good faith and did not know the true line.
3. The neighbor changed position to their detriment, typically by building costly permanent improvements.
4. Allowing the owner to assert the true line would be inequitable.

Estoppel can arise as soon as the reliance occurs. It does not require ten years.

Comparing the doctrines

Limits

• Public lands. Limitations do not run against the State or its subdivisions (Const. § 104; § 15-1-51). Public officials cannot give away public land by agreement (Const. § 95). These doctrines do not shift the lines of State land, public-trust tidelands, county or municipal land, or sixteenth section school lands (Sections 10.3 and 11.3).
• Proof. These are fact-intensive equitable claims decided in chancery. Their success depends on evidence the surveyor often gathers.

The surveyor's role

1. Retrace the record line and monument it, unless a recorded agreement or decree has fixed a different line.
2. Locate and describe the occupation line and the evidence of its origin and age (Rule 7.3, item 10).
3. Search the records for recorded boundary-line agreements, court decrees, prior plats, and any § 15-1-13(2) notices, and cite them as sources (item 9).
4. Show the discrepancy between the lines (item 9). Where owners want to settle the line, survey the agreed line and prepare a plat and description to accompany a recorded agreement drafted by counsel.

Evidence that tends to prove or defeat each doctrine

The surveyor often gathers this evidence: the age and construction of fences, historic aerial photographs showing when a fence line or clearing appeared, prior plats and county surveyor records, and interviews. Presenting it objectively lets the parties settle, or the chancellor decide, on facts.

Worked scenarios

1. Hedgerow agreement. Two owners of 1940s metes-and-bounds tracts could not find their common corners. In 1998 they agreed to treat an old hedgerow as the line and fenced it. A 2026 retracement puts the record line 14 feet east. The plat shows both lines and the 14-foot strip, cites the owners' written or recorded agreement if any, and notes the discrepancy. If the owners want certainty, the surveyor surveys the hedgerow line for a recorded boundary-line agreement.
2. Fence of convenience. A fence runs 30 feet inside the record line to keep cattle off a creek bottom, and both families have always called the creek bank "the line." Acquiescence in the fence is unlikely because neither owner treated the fence as the boundary. Show the fence as occupation and monument the record line.
3. Sixteenth section. A fence has stood 40 years inside a sixteenth section. None of the doctrines applies against the school trust, so the surveyor retraces the section line and shows the fence and its offsets (Section 11.3).