Boundary by parol agreement and boundary by acquiescence are often treated together; however, they are separate rules and require different elements of proof. Unfortunately, the courts do not always differentiate clearly between them. To add to the confusion, many opinions refer to an implied agreement when they are apparently discussing an acquiescence situation; other courts require that the parol agreement to fix the boundary must be acquiesced for a specified period of time.
Once a boundary has been fixed either by parol agreement or by acquiescence, then such agreement is conclusive against the owners and those claiming under them despite contrary evidence presented by a subsequent survey.
The burden of proof rests on the party claiming the existence of an agreed boundary, and this claim must generally be established by a preponderance of the evidence. The issue of what constitutes the boundaries of a parcel of land is a question of law; the determination of where such boundaries lie is a question of fact. (Location of division line between adjoining premises is a question of fact.) Kandlik v. Hudek 365 Ill. 292, 299 (Ill. 1937); Here the court held that the meaning of a plat is a question of law for the court. To interpret the intent of the grantor, the same rules of construction apply as in the construction of a deed. This means that every word, figure, and line must be considered and the instrument must be construed as a whole. Davis, 16 Ill. App. 3d at 335.; In Davis, the court held the question as to where the line run by a government survey lies on the ground, and whether any particular tract lies on one side or the other of that line, are questions of fact.) U S v. State Inv Co, 44 S.Ct. 289, 290 (U.S.N.M 1924); (Question as to the location of the true southern boundary of plaintiff’s land was for the jury.) McKey v. Village of Hyde Park, 10 S.Ct. 512, 513 (U.S. Ill, 1890); (Where a doubt in the application of the description of a deed to external objects arises from what is called a “latent ambiguity,” which has its origin in parol testimony and must necessarily be solved in the same way, it becomes a question to be decided by a jury what was the intention of the parties to the deed); Reed v. Proprietors of Locks & Canals on Merrimac River, 8 How. 274 (U.S.Mass., 1850); (It is for the court, in an action of ejectment, to fix the boundaries of the tract in controversy, by an examination of the whole evidence.) Varclay v. Howell’s Lessee, 6 Pet. 498 (U.S.Pa., 1832).
Cases involving a boundary agreement generally require three elements: 1) a dispute or uncertainty regarding the location of the boundary; 2) an oral or implied agreement settling the matter, and 3) possession to or recognition of the line by the parties for some period of time. Boyer v. Noirot 423 N.E.2d 274, 275 (Ill.App., 1981).
In order for the boundary agreement to be valid, it must have been made to settle a boundary dispute or uncertainty concerning the exact location of the boundary. This relates to the legal requirement of consideration in order for a contract to be valid. In the case of a boundary line dispute, the property owner who gives up land in order to settle the dispute or uncertainty provides consideration by relinquishing the property he owns. The claimant, while not relinquishing land, supplies consideration in the form of relinquishing the right to sue over the boundary dispute. Thus, both owners supply consideration by giving up either land or the right to sue when they settle their dispute or uncertainty in an agreement.