Per Curiam :
In Confederated Salish and Kootenai Tribes v. United States, 181 Ct. Cl. 739 (1967), the court held that plaintiffs stated a valid claim in paragraph 13 of their petition. This cause of action was that under the provisions of the license issued by the Federal Power Commission to the Montana Power Company — which license included the company's use of a site on the Tribes' land in the Flathead Reservation, in connection with the licensee's power project on and along the Flathead River and Flathead Lake — the defendant required the company to sell power to a federally-sponsored irrigation project at a low rate which subsidized that agency and deprived plaintiffs of the full value (including power value) of their lands used 'by the licensee. The plaintiffs seek full just compensation, including power value. At the earlier stage of the case, we held that, if the plaintiffs did suffer such a loss, they were entitled to full compensation under various Congressional enactments (181 Ct. Cl. at 743-749), and that the claim had never been settled or released (181 Ct. Cl. at 749-752). Since the parties were in dispute whether a loss was actually suffered, we remanded the case for trial (or other appropriate proceedings) on that issue (181 Ct. Cl. at 752).
A trial was then held at which exhibits and oral testimony were introduced. On the basis of this record, the trial commissioner concluded that the plaintiffs had failed to prove that they "were deprived of the full power value of the Tribes' land used by the licensee". The case is again before us on plaintiffs' exceptions to the commissioner's report.
Unfortunately, the record, as it comes here, seems to us inadequate for final disposition of the case. The existence and amount of the plaintiffs' loss, if any, has not been properly canvassed. This is primarily because the plaintiffs misapprehended what they were expected to prove, and accordingly their proof does not jibe with the applicable rule of damages. Their showing on value was directed solely to the amount it would have cost the Federal Government to purchase from the Montana Power Company, under certain of that company's regular 1930 rate schedules, the block of 15,000 horsepower which the license required the company to sell at relatively low rates to the United States for the benefit of the irrigation project. As the trial commissioner indicated in his memorandum opinion, this is a measure of what the United States gained — i.e., what the United States would have had to pay for the power if it had had to buy it at regular rates — not a measure of what the plaintiffs lost from the taking of their lands (including the lands' power value). The correct test, of course, is what, if anything, the Tribes lost from the requirement that the licensee sell the 15,000 horsepower to the Federal Government at the lesser rates specified in the license. No effort was made to show that detriment. Obviously, the 1930 power company schedules, on which plaintiffs have relied, have no real connection with the extra amount which a licensee (the Montana Power Company or any other) would have been willing to pay the Indians, in an arm's-length transaction, in the absence of the requirement for the special sale of the 15,000 horsepower. But that additional sum is the only true measure of the Tribes' loss, if there was any. It has not yet been found.
One solution would be to say that the plaintiffs have had their chance, as the claimants, to prove their loss, and having failed to do so under the proper standard they should now be dismissed, without being accorded another opportunity. This is the stand the trial commissioner may have taken. We do not, however, follow that course for several reasons. The first is that the present record, defective though it is, does indicate that the power company probably incurred an annual loss in supplying the 15,000 horsepower to the Federal Government. From that significant fact it would appear, at least 'prvma facie, that the licensee would probably have been willing to raise its payments to the Indians, to some extent, if that loss were removed. The serious problem posed by this fact of a substantial annual loss for the licensee on the required sale calls for further exploration to see whether, in fact, the loss on the sale of this block of 15,000 horsepower would 'have any effect on the rentals payable to the Tribes.
Second, our prior opinion was not explicit on the proper measure of plaintiffs' loss and, consequently, may not have warned plaintiffs against the course they followed at the trial. Since the parties put no emphasis, at that point in the case, on the measure of the loss, and we were remanding for trial on that issue, we did not treat expressly with the standard. Though we see nothing incorrect or misleading in our opinion, the incidental references to "power value" — which were pertinent to the then issue of whether Congress had agreed to pay for the power value incident to the Tribes' land — may have been taken by the plaintiffs as sanctioning the incorrect measure they proposed at trial, i.e. the market value of the power to be sold by the power company to the Federal Government.
Third, we are not certain that the trial commissioner adopted tbe correct standard for the loss to the Indians from the compulsory sale to the United States. Much of his short memorandum opinion reads as if he probably did apply the proper measure, but he does not spell out his reasoning in enough detail for us to be sure. For instance, he does not refer to, or deal with, the significant fact that the company probably suffered a substantial loss on the lower-price sales for the benefit of the irrigation project.
Finally, we cannot forget that this is a litigation brought by Indian Tribes to redress an alleged wrong by the Government which has long supervised their affairs. Though we do not lean over backwards in such a case, we are somewhat more lenient in procedural matters than we might be in other classes of cases in which the relationships of the parties are not so special.
For these reasons, we do not hold the plaintiffs strictly to their failure, up to now, to prove the existence and the amount of any loss they may have incurred. Instead, we remand the case to a trial commissioner for a new trial, vacating the prior commissioner's opinion and findings so that the parties can start afresh and direct their presentation to the correct measure of damages.
So that there be no mistake, we stress that we are in no way holding that plaintiffs have yet proved any loss, let alone the amount of such a loss. The issue of the existence of a loss, as well as of the amount, remains to be tried again. To recover, plaintiffs must prove that a supposititious willing buyer desiring to develop the site for power purposes, and able to obtain the necessary license, would have paid, and a willing owner would have accepted, a higher rental than the amount actually paid, if the former had not been burdened with the necessity to sell at the prescribed rate the block of 15,000 horsepower to the Federal Government, and then the plaintiffs must show the probable amount of that excess.
The commissioner's memorandum opinion and findings, filed December 3, 1968, are vacated, and the case is returned to a trial commissioner for further proceedings in conformity with this opinion.
At the hearings before the Federal Power Commission, prior to the award of the license, a representative of the company testified that the annual out-of-poelcet loss would be $62,500. Assistant Commissioner of Indian Affairs Scatter-good calculated that the loss would be $25,336. The present record does not contain enough information to resolve this conflict.
The present record contains opposing contemporary conclusions on this point — Assistant Commissioner Scattergood thought that the Indians' return was not affected, while others thought it was and would have to be — but there is very little analysis of the problem, and none in any depth.
At that juncture, the main question was whether Congress, although not compelled by the Constitution to compensate the Indians for the water power value of their lands taken for the power project, did undertake to do so in various pieces of legislation, particularly the Act of March 7, 1928, ch. 137, 45 Stat. 200, 212-213. The court held that Congress did so intend.
It may also be that tbe commissioner believed that tbe United States gave more of a Quid pro quo for these sales than it actually gave. Plaintiffs insist that be made factual errors in this connection.
Tbe court has denied, as untimely, a post-argument motion by the Flathead, Mission and Jocho Valley Irrigation Districts to file a post-argument brief amici curiae in support of the defendant. However, these parties are hereby granted leave to participa-te as amici cwiae in the further proceedings before the commissioner, if they wish to do so.