(concurring in the result).
I agree that this fence was not established by acquiescence as the boundary line because there is no evidence that the defendants or their predecessors acquiesced in it as such. Such acquiescence requires assent or consent by the owners of adjoining tracts of land that a known line which is clearly marked by a fence or other monuments is the boundary line between such adjoining tracts by silently treating it as such and failure to make any protest.1 It does not require an express agreement to that effect., Here, except for the last four or five years prior to the commencement of this action, there is no evidence that the defendants or their predecessors either lived on their property,, knew of the fence line, occupied their land only up to the fence line or in any manner indicated by silence or otherwise that they assented or consented to the fence line as the boundary. Thus the evidence failed to show acquiescence and the court correctly found that issue in plaintiff’s favor.
However, I do not agree that a showing of a boundary line by acquiescence can be defeated merely by evidence which negatives the existence of an express agreement to that effect. Much is said in the cases: about an agreed boundary line, but I think that acquiescence alone is sufficient in a proper case if it exists for the required' period of time to establish a boundary line- and that it is immaterial whether or not there is an express agreement. In other words as stated in the prevailing opinion “the court indulges a fiction” 2 from proof *242of the necessary acquiescence and that the doctrine recognizes it as a fiction which will not be changed by express proof that no such an agreement exists. Thus the talk of an agreement is merely the legal or roundabout method used by the courts in holding that acquiescence alone is sufficient and it is immaterial whether such an agreement was ever reached.
To that effect is Holmes v. Judge,3 one of our earliest and most carefully considered cases. There the trial court found that there was no express agreement probably because the evidence showed that the fence and walls of the buildings which were acquiesced in as marking the boundary line were built by tenants and not by the owners of the adjoining lots. In answering the question “Is such an agreement necessary in cases of this kind?” we quoted with approval from Baldwin v. Brown,4 as follows:
“The supposition of such an agreement (referring to an agreement establishing a boundary line) in cases of long acquiescence in an established line . is, as I apprehend, entirely superfluous. The acquiescence in such cases affords ground, not merely for an inference of fact to go to the jury as evidence of an original parol agreement, but for a direct legal inference as to the true boundary line. It is held to be proof of so conclusive a nature that the party is precluded from offering any evidence to the contrary. Unless the acquiescence has continued for a sufficient length of time to become thus conclusive, it is of no importance. The rule seems to have been adopted as a rule of repose, with a view to the quieting of titles, and rests upon the same reason as our statute prohibiting the disturbance of an adverse possession which has continued for twenty years. * * * ” (Italics taken from the quotation.)
This quotation clearly holds that where a fence or other monument has been acquiesced in as the boundary line for the required period of time, qn agreement to that effect is entirely superfluous, that the true, boundary line will be inferred therefrom as a matter of law, and that evidence that there was no such agreement is inadmissible because it is immaterial. In other words where adjoining land owners acquiesce in a fence line or other monument as the boundary line between their properties for the required length of time it becomes the boundary line as a matter of law even though there was no express agreement to that effect. Of course if the parties knew that the line which they acquiesced in was not the true boundary5 or if they expressly agreed that the boundary line would be later determined and the fence or monuments were placed only temporarily until that time6 and possibly if *243the line was acquiesced' in as the boundary line by mistake 7 a boundary line by acquiescence would -not be established.
Although much is said in the cases about estoppel and express agreements on a boundary line the real justification for the doctrine is to stabilize titles to real estate, to prevent uncertainty and litigation over the location of the boundary lines.8 I am not sure that an express contract without the required period of acquiescence has ever been held to establish a boundary line at a place other than the true boundary line. Certainly there are no Utah cases which so hold,9 and it is equally certain that the doctrine is not dependent on a true estoppel although there might be cases where estoppel also exists.10
If the purpose and object of this doctrine is to stabilize titles and prevent uncertainty and litigation, then that purpose will be readily defeated unless we avoid all technical and fine distinctions. Otherwise the application of this doctrine will probably create the very thing it was intended to eliminate.11 For many years after the case of Holmes v. Judge, supra, the doctrine seemed to be quite clear and little difficulty was encountered, but in recent years a lot of uncertainties have crept into it until now the whole doctrine is shrouded in doubt.-
As pointed out in the prevailing opinion there are a number of cases which point out as one of the grounds for defeating a boundary line by acquiescence, that the evidence tends to show that there was no express agreement. However, I think in all of those cases this theory was not necessary in order to reach the result, because there were other grounds pointed out in the opinion which were sufficient to sustain the result.12 I think that there are a number of cases which would have required a contrary result if this theory had been invoked.13 I therefore disagree with the *244part of the prevailing opinion which relies on the fact that the evidence is inconsistent with an express agreement on the fence line as the boundary as a ground for defeating the establishment of a boundary line by acquiescence.
. See Bouvier’s Law Dictionary, Rawle’s Third Revision, Acquiescence; 1 Words and Phrases, Acquiesce; Acquiescence, pages 631 to 639; Chicago & A. R. Co. v. Myers, 86 Ill.App. 401; Pierce’s Adm’r v. Pierce, 66 Vt. 360, 29 A. 364, 366; Thompson v. Simmons, 143 Ga. 95, 84 S.E. 370; Griffin v. Brown, 167 Iowa 599, 149 N.W. 833; Union Central Life Ins. Co. v. Caldwell, 68 Ark. 505, 58 S.W. 355.
. See Brown v. Milliner, Utah, 232 P.2d 202, at page 207; Dragos v. Russell, Utah, 237 P.2d 831, at page 833. In both of these cases the agreement is referred to as a “fiction” and is attributed to an explanation made by Mr. Justice Latimer in Glenn v. Whitney, 116 Utah. 267, 209 P.2d 257, but I do not find that, term used in that case.
, 31 Utah 269, 87 P. 1009.
. 16 N.Y. 359, at page 363.
. Tripp v. Bagley, 74 Utah 57, 276 P. 912, 69 A.L.R. 1417.
. See Rieske v. Hoover, 53 Utah 87, 177 P. 228.
. See Holmes v. Judge, supra, Glenn v. Whitney, supra, Blanchard v. Smith, Utah, 255 P.2d 729. These cases seem to recognize that mistake might defeat a boundary line by acquiescence but they fail to point out the exact nature of the mistake required to have that effect. The question was not before the court in any of those cases and so what was said on that question was dicta.
. See Holmes v. Judge, supra, Perry Estate v. Ford, 46 Utah 436, 151 P. 59; Young v. Hyland, 37 Utah 229, 108 P. 1124; Rydalch v. Anderson, 37 Utah 99, 107 P. 25, practically all of the cases on this question so hold.
. See an article to come out shortly in the Utah Law Review by David Martin Oook where the Utah cases are cited. •
. If the owner of an adjoining tract stood by and watched the purchase and sale of his neighbor’s property knowing that the purchaser had reason to and did believe that a fence marked the boundary between the two lots he might well be estopped to deny that such was the boundary line, but none of the cases that I have read contain all the necessary elements of such an estoppel.
. See Article referred to in Note 9 above.
. See cases cited in the prevailing opinion, also see Article cited in Note 9 above.
. See Holmes v. Judge, supra; Willie v. Local Realty Co., 110 Utah 523, 175 P.2d 718; and the recent case of Blanchard v. Smith, Utah, 255 P.2d 729. Each of these cases held that a boundary line by acquiescence was established although *244the fence and monuments which marked the boundary line were erected under circumstances which indicated that there, was no express agreement.