Dissenting on Motion for Rehearing.
I have changed my view on what the outcome of this case should be, but because my first opinion was so persuasive and *365well-reasoned, the other two judges of this Court continue to embrace the holdings in the initial opinion. While the initial opinion is essentially correct in the issues covered, Geo Viking correctly points out in its motion for rehearing that we did not fully address its point of error on the failure of the trial judge to instruct the jury on the proper measure of damages. It discussed only the rule of capture and not the problem of obtaining minerals by trespassing. An examination of this issue leads to a different disposition of the case; therefore, I respectfully dissent.
Geo Viking complained that the trial court erred in failing to give a limiting instruction to the jury that it was not to consider as a part of damages oil and gas that was obtained by fracing beyond the boundary of the unit owned by Tex-Lee. Geo Viking requested the following instruction, which was refused by the court:
In answering Question No. 5, you shall not consider or include the value of the oil and gas reserves, if any, outside the 80 acre unit that would have become recoverable from the White 1 well because of any fracing beyond the boundaries of such unit. In other words, in estimating the value of such oil and gas reserves, if any, you shall consider only those reserves that would have become recoverable as a result of fracing within the boundaries of the lease in question.
This instruction was requested in conjunction with the damage issue, and Geo Viking has a specific point of error on appeal complaining about the court’s failure to submit that issue.
Geo Viking takes the position that the measure of Tex-Lee’s damage to properly sandfrac the well would only be the loss of the oil and gas that Tex-Lee could legally obtain through that process. Geo Viking contends that to the extent that oil and gas were obtained by trespass when the frac-ing process went under the land of other property owners, Tex-Lee could not claim that portion of oil and gas as damages. Tex-Lee contends that Geo Viking should have raised this in its pleadings as an affirmative defense of illegality of contract pursuant to Tex.R.Civ.P. 94. I disagree. Geo Viking is not contending that the contract is unenforceable because it was illegal or against public policy, nor has it taken the position that any portion of the contract is invalid for illegality.
The rule of capture provides that the owner of a tract of land acquires title to the oil and gas which he produces from wells drilled thereon, even though such oil and gas has migrated from adjoining lands. Halbouty v. Railroad Commission, 357 S.W.2d 364 (Tex.1962). However, the rule of capture is permissible only “so long as the producing well does not trespass.” See Williams & Meyers, Oil and Gas Terms, 869 (7th ed. 1987).
In dictum,3 the Texas Supreme Court stated that fracing under the surface of another's land constitutes a trespass. Gregg v. Delhi-Taylor Oil Corp., 344 S.W.2d 411 (Tex.1961). The Court in Gregg pointed out that fracing under another person’s lands had all the necessary elements to be a trespass and found that it was comparable to slant-well drilling that bottomed on a neighboring tract, which the court had found to be a trespass and subject to injunctive relief in Hastings Oil Co. v. Texas Co., 149 Tex. 416, 234 S.W.2d 389 (1950). We agree that Tex-Lee could not claim as damages loss of oil and gas to which it was not entitled.
Although Tex.R.Civ.P. 277 gives the court discretion to submit issues broadly, this discretion is not boundless. Johnson v. Willis, 596 S.W.2d 256, 262 (Tex.Civ. App. — Waco 1980, writ ref’d n.r.e.). Damages must be measured by a legal standard which serves to guide the factfinder in determining the amount of compensation required. The proper measure of damages is a question of law for the court but the charge should limit the jury’s consideration to facts that are properly a part of the damages allowable. Mangham v. Hall, *366564 S.W.2d 465, 468 (Tex.Civ.App. — Corpus Christi 1978, writ ref d n.r.e.). The charge to the jury must be sufficient to enable the jury to make an assessment of damages on proper grounds and proper legal principles. Jackson v. Fontaine’s Clinics, Inc., 499 S.W.2d 87 (Tex.1973). There was evidence stating that the fracing process went more than 2,500 feet from the well site, which was far beyond the boundaries of the unit and outside the leasehold, and that it should have gone another 1,000 feet so that it could have intersected one of the major faults. Thus, the jury had before it evidence upon which it may have based all or a portion of its damages for a loss in oil and gas to which Tex-Lee was not legally entitled to obtain. Pursuant to Tex. R.App.P. 81, I have determined that this error was reasonably calculated to cause and did cause the rendition of an improper judgment.
The judgment of the trial court should be reversed, and the case remanded for a new trial.
. These statements in Gregg v. Delhi-Taylor Oil Corp., 344 S.W.2d 411 (Tex.1961), are dicta, because the issue decided by the court was whether the Railroad Commission or the District Court has jurisdiction in the case.