The Texas court has recognized two legitimate standards that justify upholding a survey - original undisturbed monuments, or "best available evidence."
As stated in the Texas decision Arkansas Co. Nav. Dist. No. 1 v. Johnson: No 13-05-563-CV (2008):
In a boundary dispute, the ultimate object of the trier of fact is to determine the "true location of the line in dispute." Mortgage Inv. Co. of El Paso v. Bauer, 493 S.W.2d 339, 342 (Tex. Civ. App.-El Paso 1973, writ ref'd n.r.e.), overruled on other grounds, Martin v. Amerman, 133 S.W.3d 262, 268 (Tex. 2004). Moreover,
[w]hen this cannot be done with reasonable certainty due to the lapse of time or the obliteration of the evidence of the original locater, it is not only permissible, but, out of necessity, required that the courts resort to any evidence tending to establish the place of the original footsteps of the surveyor which meet the requirement that it is the best evidence of which the case is susceptible.
Bauer, 493 S.W.2d at 342. In other words, where "exactness [is] difficult of attainment, [it] should not be insisted upon, to the destruction of right." State v. Humble Oil & Ref. Co., 187 S.W.2d 93, 107 (Tex. Civ. App.-Waco 1945, writ ref'd w.o.m.) (citing Hamilton v. Menifee, 11 Tex. 718, 749 (1854)).
Although the parties do not direct us to, nor can we find, any Texas case interpreting the phrase "substantially correct" as used in a boundary dispute jury charge, courts have clarified the phrase in other contexts. In fact, as noted above, Texas Rule of Civil Procedure 278 provides that a trial court's failure to submit an issue shall not be grounds for reversal of the judgment unless the issue was previously tendered by the appellant in "substantially correct" wording. TEX. R. CIV. P. 278. In that context, the Texas Supreme Court has stated that:
Substantially correct . . . does not mean that it must be absolutely correct, nor does it mean one that is merely sufficient to call the matter to the attention of the court will suffice. It means one that in substance and in the main is correct, and that is not affirmatively incorrect.
[Emphasis in Original]
