Appeals from the United States District Courtfor the District of ArizonaEarl H. Carroll, District Judge, PresidingArgued and SubmittedOctober 17, 1995--San Francisco, CaliforniaFiled July 8, 1997Before: Mary M. Schroeder, Betty B. Fletcher, andPamela Ann Rymer, Circuit Judges.Opinion by Judge Schroeder; Partial Concurrence andPartial Dissent by Judge Fletcher
_____________________________OPINION SCHROEDER, Circuit Judge:I. INTRODUCTIONThese appeals are part of the long running and emotionscarring controversy between the Navajo Nation and the HopiTribe, in which the legislative, executive and judicialbranches of the United States have all figured prominently.The dispute has centered on the ownership, control and use ofnearly 2 million acres of the Native American reservationland occupying the northeast portion of Arizona and neigh-boring portions of Utah and New Mexico.These particular cases arise out of specific remedial provi-sions of the Navajo-Hopi Settlement Act of 1974, 25 U.S.C.S 640d, et seq. (1980) (the "Settlement Act"). The SettlementAct allows partition of reservation land that the courts haddeclared jointly shared by both tribes, but which had beenused for grazing exclusively, and excessively, by the Navajo.The Navajo overgrazing was fostered, in large part, by theDepartment of Interior, which refused to grant the Hopi graz-ing permits while simultaneously providing the Navajo withpermits for more grazing than the land could reasonably sup-port. Hamilton v. MacDonald, 503 F.2d 1138, 1146 n.10 (9thCir. 1974) (explicitly affirming the district court's factualfindings regarding the government's responsibility for Navajoovergrazing). In the 1974 Act, Congress expressly authorizedlitigation between the Hopi and the Navajo for enumerateddamages; Congress intended for money to leaven the land-related inequalities between the Hopi and the Navajo.The background of this litigation has been recited in nearly35 years of court decisions and in numerous books andperiodicals.1 We provide only a summary here.In 1882, President Chester Arthur by executive order cre-ated a 2.5 million acre reservation for the Hopi and "suchother Indians as the Secretary of Interior saw fit to settlethereon." Exec. Order of Dec. 16, 1882, reprinted in, Healingv. Jones, 210 F.Supp. 125, 129 n.1 (D. Ariz. 1962), aff'd, 373U.S. 758 (1963). Under this executive order, the Hopi Tribeenjoyed the right to use and occupy the entire reservation. Bycontrast, the Navajo who had already settled in the reservationdid not gain any immediate rights to the land. Nevertheless,the Navajo continued to use and occupy parts of the 1882 res-ervation. By 1900, the Navajo population had increased to1,826. Healing, 210 F.Supp. at 145. In 1920, it reachedapproximately 2,600, and by 1958, it exceeded 8,800. Id.Despite the Navajo's continued use of the reservation, theirright to use the land during this period was unclear, and thiscaused an ongoing and bitter dispute.In 1958, Congress authorized litigation to settle title to the1882 reservation. Id. at 130. A three-judge district court thusexamined the question in Healing and found that the Navajohad no right to use the land until 1931, when the Interior Sec-retary impliedly exercised his authority under the executiveorder to "settle" the Navajo on the reservation. Id. at 157. TheHealing court further observed that all Navajo who immi-grated to the reservation between 1931 and 1958 were alsoimpliedly "settled" in the reservation. Id. at 169. Healing heldthat the Hopi occupied the area known as "land district 6"exclusively, but that the two Tribes held a joint, undividedand equal interest in the remainder, known as the Joint UseArea (JUA). Id. District 6 is 600,000 acres. The JUA isgreater than 1.8 million acres.Unfortunately, the 1962 order did not resolve the dispute.Between 1962 and 1972, the federal government continued togrant grazing permits to the Navajo, while rejecting all Hopiapplications. Hamilton, 503 F.2d at 1146 n.10. At the sametime, the Navajo intimidated the Hopi and mutilated their cat-tle. Id. Together, the federal government and the Navajoexcluded the Hopi from what Healing had declared a "jointuse area."The Hopi thus brought a supplemental action in which theyobtained an order of compliance and a writ of assistanceenforcing the Healing decision. Our decision affirming theorder and the writ, Hamilton, 503 F.2d 1138, documents ingreater detail the exclusion of the Hopi from the JUA. InHamilton, we noted that although the permits enabled theNavajo only to eke out an existence, terrible and destructiveovergrazing occurred nonetheless; the carrying capacity of therange was simply insufficient. Id. at 1145 (JUA is "an over-grazed, harsh and inhospitable area which yields little abovea subsistence living").The Hamilton order required the Navajo to, among otherthings, reduce its livestock and to allow the Hopi to share theland. Id. at 1142 n.2. It also required the federal governmentto cancel all grazing permits and issue new ones, without giv-ing either the Hopi or the Navajo permits for more than theirhalf of the land's carrying capacity. Id. Additionally, the orderrequired the government to adopt a plan to achieve the broadgoals of the compliance order, including restoration of therange, within 90 days. Id. Both the government and the Nav-ajo failed to do as ordered. In 1974, the Navajo were held incontempt of court. Sekaquaptewa v. MacDonald, No. Civ.579 PCT (JAW) (D. Ariz. May 29, 1974), aff'd, 544 F.2d 396(9th Cir. 1976), cert. denied,
430 U.S. 931
(1977). At thattime, the Navajo's livestock exceeded, by approximatelyseven times, the JUA's carrying capacity. Id. at 3-4.Against this background, Congress in 1974 passed the Set-tlement Act, authorizing partition by court order in the eventmediation failed, which it did. A court order of partition wasentered, and after appeal and remand, see Sekaquaptewa v.MacDonald, 575 F.2d 239 (9th Cir. 1978), was reconfirmed.The Settlement Act itself called for partition to achieve asequal a division as was practicable, 25 U.S.C. S 640d-5(d),while at the same time expressly directing that populationcenters should not be divided, 25 U.S.C. S 640d-5(b). Thelegislation also called for measuring the value of the land, forpurposes of division, as if the grazing capacity were restored.25 U.S.C. S 640d-5(d). In an effort to adjust any imbalancethat might result from an unequal division, and to compensatethe Hopi for both past exclusion from grazing the land anddamage done to the land by Navajo overgrazing, Congressauthorized several actions for money damages. So that theHopi and the Navajo could sue one another and join theUnited States as a party, Congress waived immunity for allthree sovereigns. 25 U.S.C. S 640d-5.In Hopi Tribe v. Navajo Tribe, 46 F.3d 908 (9th Cir.) (the"rent case"), cert. denied, 116 S.Ct. 337 (1995), we affirmeda judgment awarding the Hopi rent, pursuant to S 640d-15(a)of the Settlement Act, for the post-partition presence of Nav-ajo homesites on the Hopi half of the partitioned land. Wealso remanded the Hopi's award of rent for the post-partition(1979 to 1984) grazing of Navajo cattle and sheep on theHopi half of the partitioned land, so that the district courtcould review the merits of the Navajo challenge to the award.We now have three Settlement Act cases before us onappeal. We review first a judgment entered in favor of theHopi, pursuant to S 640d-17(a)(2), for the "fair value of thegrazing and agricultural use" by the Navajo of the Hopi's one-half interest in the JUA from 1962 to 1979; this is known asthe "use case." The second appeal, known as the "oweltycase", arises under S 640d-5(d), in which Congress authorizedan action for the difference in value between the land awardedto the Hopi Tribe (the HPL) and the land awarded to the Nav-ajo Nation (the NPL). The district court ruled the division wasroughly equal and entered judgment denying any relief. In thethird appeal, we consider an action pursuant toS 640d-17(a)(3) by the Hopi against both the United States and the Navajoto recover damage to the JUA caused prior to partition (the"damage case"). In the damage case, the district court enteredjudgment against the Navajo but refused to hold the federalgovernment liable, finding that the United States had notacted unreasonably in its efforts to protect the JUA from dam-age.The Navajo appeal the judgment in the use case and theNavajo and the Hopi both appeal the judgments in the oweltyand damages cases. We affirm the use case in its entirety, andin large part, we affirm the owelty and damages cases as well.We discuss each case separately.II. THE USE CASE, No. 94-17022A. BackgroundThe district court awarded the Hopi $18,187,132 for theNavajo's combined grazing and agricultural use of the Tribe'sone-half interest in the JUA from 1962 to 1979. The case waslitigated pursuant to 25 U.S.C. S 640d-17(a)(2), whichallowed the Hopi to recover one-half the "fair value of the[Navajo] grazing and agricultural use" between the time ofthe JUA's creation (Healing decision of September 28, 1962)and the partition of the JUA on April 18, 1979. 2In this appeal, the Navajo's principal contention is that theSettlement Act itself is unconstitutional because it divests theNavajo of a vested property right to graze animals on theentire JUA. Additionally, the Navajo, for the first time onappeal, contend that the district court lacked jurisdictionbecause the determination of the fair value in this case consti-tutes a non-justiciable political question. The Navajo alsochallenge several evidentiary rulings and factual findings con-cerning the valuation of their grazing and agricultural use. Weaffirm the judgment.B. Constitutional ChallengesRelying on the due process clause of the Fifth Amendment,the Navajo argue that the Settlement Act undermines theirproperty rights, as secured by the judgment in Healing. TheNavajo also suggest that the statute is a retroactive impair-ment of their rights under the Contracts Clause of Article I.Whether the statute is constitutional is a question of lawreviewed de novo, and as we have recently said, a courtshould invalidate a statutory provision "only for the mostcompelling reasons." Gray v. First Winthrope Corp., 989 F.2d1564, 1567 (9th Cir. 1993) (internal quotations omitted).[1] The common flaw in all of the Navajo's constitutionalarguments is that the Navajo never had, either by court decreeor contractual promise, an unfettered right to use the JUA tothe exclusion of the Hopi. Rather, the Healing decisiongranted the Hopi and the Navajo joint and undivided interestsin the JUA. Therefore the statute is a legitimate effort by Con-gress to implement the Healing decree, and to rectify wrong-ful conduct that has occurred in the wake of Healing.[2] The Navajo next argue, for the first time on appeal, thatthe district court lacks jurisdiction to determine the "fairvalue" of "grazing and agricultural use" because this is a non-justiciable political question. Assuming the Navajo did notwaive the political question issue, their contention is withoutmerit. The Navajo position boils down to an assertion that thedetermination of "fair value" is not an issue that courts arecapable of resolving. See Baker v. Carr,
369 U.S. 186
, 217,82 S.Ct. 691, 710 (1962) (issue may be a non-justiciable polit-ical question if it lacks judicially discoverable and manage-able standards for resolution). The Navajo, however,recognize that courts frequently address the concept of "fairmarket value." See, e.g., Eales v. Environmental Lifestyles,Inc., 958 F.2d 876, 880 (9th Cir. 1992), (calculating "fair mar-ket value" of architectural plans); cert. denied, 113 S.Ct. 605(1992) Doherty v. C.I.R., 16 F.3d 338 (9th Cir. 1994) (calcu-lating "fair market value" of painting); Seravalli v. U.S., 845F.2d 1571 (Fed. Cir. 1988) (estimating "fair market value" ofreal property). We see no material difference between evalu-ating "fair value," as set forth in the Settlement Act, and eval-uating "fair market value," the more common standard. Seealso Koohi v. United States, 976 F.2d 1328, 1332 (9th Cir.1992) ("damage actions are particularly judiciallymanageable"), cert. denied,
508 U.S. 960
(1993).[3] For similar reasons, we are not swayed by the argumentthat the "fair value" determination is non-justiciable becauseit calls for a "policy determination of a kind clearly for non-judicial discretion." See Baker,
369 U.S. at 217
, 82 S.Ct. at710. Congress already made the policy decision that the Nav-ajo should compensate the Hopi for excluding them from theJUA. What Congress left for the courts, calculating "fairvalue," is within the expertise of the judiciary.[4] Finally, the Navajo, again citing Baker, maintain that"the determination [of fair value] is impossible withoutexpressing a lack of `respect' due" the Executive Branchbecause the Secretary of the Interior decided not to charge theNavajo for grazing privileges. This argument is misplaced. Asthe Hopi point out, there is no indication that the ExecutiveBranch ever took the position that the Navajo need not paythe Hopi for their extraordinary overgrazing of the JUA. TheExecutive Branch's decision that the Navajo need not pay thefederal government for grazing permits is consistent with theCongressional mandate that the Navajo compensate the Hopifor overgrazing. In sum, we reject each of the Navajo's con-stitutional challenges.C. Evidentiary challenges to expert testimonyThe Navajo contest the district court's admission of Hopiexpert Dr. John Workman's testimony regarding the fair valueof Navajo grazing (as opposed to agricultural growth) on theJUA. They argue that Workman lacked sufficient foundationto support his testimony, since he is not a real estate appraiserbut an economist. They further contend that his methodologydid not satisfy the test for expert scientific testimony inDaubert v. Merrill Dow Pharmaceuticals, Inc.,
509 U.S. 579
,113 S.Ct. 2786 (1993). We review a decision to admit experttestimony for abuse of discretion. Dang Vang v. Vang XiongX. Toyed, 944 F.2d 476, 480 (9th Cir. 1991)."A trial court hasbroad discretion to admit and exclude expert testimony [underFed. R. Evid. 702] and its decision will be sustained unless itis `manifestly erroneous.' " Id. (citation omitted).[5] The court was well within its discretion to conclude thatDr. Workman is qualified to offer an opinion regarding thefair value of Navajo grazing. Dr. Workman has been a profes-sor of Range Economics for twenty-five years, teachingcourses in "rangeland appraisal" and "range economicanalysis." He has written a textbook on range economics anddozens of peer-reviewed publications on subjects related tohis testimony. He has been qualified as an expert on rangeeconomics in a case where he gave similar valuation testi-mony. See White Mountain Apache Tribe v. United States, 11Cl. Ct. 614, 665-66 (1987) (qualifying Dr. Workman as "anexpert in appraisal and range management" and characterizinghis proposed measure of damages as "especially persuasive"),aff'd, 5 F.3d 1506 (Fed. Cir. 1993), cert. denied, 114 S. Ct.1538 (1994).[6] The district court thoughtfully examined the methodol-ogy and opinion of each expert, and accepted Dr. Workman'smeasure of damages only after making appropriate downwardadjustments. The Navajo's reliance on Daubert is misplacedbecause Dr. Workman's testimony derives from his relativelystraightforward application of range economics, rather than ona novel scientific theory. See Dang Vang, 944 F.2d at 482.[7] The Navajo also challenge the district court's decisionto admit testimony from Hopi expert Robert Francy, anappraiser, on the value of corn grown on the JUA. Francy for-mulated his opinion from what others told him about cornprices. The Navajo argue that this constituted an improper useof inadmissible hearsay. However, the Navajo failed to raiseany timely, specific hearsay objection to the expert's testi-mony and thus waived their right to assign error on appeal.See Fed. R. Evid. 103. The record, moreover, reveals that nostatements from third parties were admitted for their truth.The third party statements only provided the Hopi expert withbackground information about corn sales, from which he fash-ioned his testimony. Such reliance is permissible, sinceexperts in the field, i.e. appraisers, regularly go to third partiesfor sales figures, as the Hopi expert did here. See Fed. R.Evid. 703.D. Challenges to the district court's valuation calculations The district court separately valued Navajo "agricultural"use and "grazing" use, as contemplated by the statute. 25U.S.C. S 640d-17(a)(2). The Navajo challenge the agriculturaluse valuation on two grounds. First, they argue that the dis-trict court clearly erred when it adopted Hopi expert RobertFrancy's conclusion that the Navajo had actually farmed theJUA between 1962 and 1979. They contend that Francy'sconclusion was based only on speculation. However, therecord shows that Francy's conclusion was premised on tworeports from the Bureau of Indian Affairs (BIA), aerial photo-graphs, maps, documents, and personal spot checks. The courtdid not clearly err. Second, the Navajo contend that there wasinsufficient evidence to support a finding that there was acommercial market for the approximately 200,000 pounds peryear of corn attributable to Navajo farming. This argument,however, spuriously assumes that the corn consumed by theNavajo themselves lacks value. The evidence clearly estab-lished that the market for most of the corn was in the natureof personal consumption, and only a small percentage of thecrops were sold commercially. Thus, the evidence supporteda finding that there was a market for the corn.[8] The Navajo challenge to the district court's calculationof the value of Navajo grazing on the JUA is slightly morecomplicated than their other contentions, but no more valid.First, the Navajo contend that the value of their grazing on theJUA should be computed from the land's carrying capacity,i.e., the amount of grazing the land can sustain without irrepa-rable damage. This is how ranch land is typically valued forleasing purposes. Because longtime Navajo overgrazing dras-tically decreased the carrying capacity of the JUA, the rentalvalue of the land between 1962 and 1979 was only one-fifththe typical rate in Arizona. The district court thus rejected theNavajo's approach and estimated the actual amount of grazingfrom the number of Navajo animals on the JUA. At times,actual grazing by Navajo livestock exceeded the carryingcapacity by approximately seven-fold. The district court thenvalued the Navajo's use of the land by reference to the actualamount of Navajo grazing. The Navajo argue that in so doing,the district court improperly charged them more than theywould have paid on the open market, as the open market rateis pegged to carrying capacity, a lower figure. As the Hopipoint out, consumption beyond the carrying capacity shouldexact a premium charge. The district court did not clearly errwhen it charged the Navajo for this excessive use.[9] Second, the Navajo argue that the court overestimatedthe number of animals on the JUA. The district court countedthe number of animals in units of cattle. For most years, thecourt converted sheep to cattle using a ratio of five sheep perone head of cattle, and adjusted downward for low animalweight. The court did not make these adjustments for 1966,1968 through 1971 and 1974, because it lacked informationabout the number of sheep and the weight of cattle on therange. The Navajo contend that the district court should havemade the 5:1 conversion and the weight adjustment duringthese years because it had sufficient information. The record,however, reveals that the court did not have precise sheepcounts during those years, and therefore could not make anaccurate conversion. In addition, the court had information ononly three cattle sales for those years, and therefore could notaccurately adjust downward for low animal weight. Thecourt's estimates of the number of animals on the JUA werenot clearly erroneous.[10] Third, the Navajo argue that the district court errone-ously valued grazing by using adjusted private Arizona leaserates instead of federal land lease rates. There were, however,no federal rates between 1962 and 1972; therefore, rates forthose years could be estimated only through statistical projec-tions. Moreover, federal rates reflect policy decisions, notmarket dynamics. The district court's use of private Arizonarates was not clearly erroneous. We affirm the district court'saward to the Hopi in the use case.III. THE OWELTY CASE, Appeal Nos. 94-17031,95-15015A. BackgroundOwelty is a sum of money paid by one former joint tenantto another after a partition results in an unequal division oftheir land; the owelty compensates the former tenant whoreceived the lesser value for the disparity. See Black's LawDictionary (4th Ed.); 68 C.J.S. Partition S 142 at 232-3 (1950& 1988 Supp.); 59A Am.Jur.2d Partition SS 2, 253 (1987). Inthis owelty case, the district court held that after partitionthere was no statistically meaningful difference in valuebetween the Hopi half of the land and the Navajo half. Thus,it ordered no owelty award.[11] The owelty action was brought pursuant to S 640d-5(d) of the Settlement Act, which authorizes the district courtto award damages for any difference in value between thehalves of the partitioned land with "improvements and graz-ing capacity fully restored."3 The Hopi appeal from the judg-ment, arguing that the district court undervalued the Navajoland because it misinterpreted the owelty statute. The Hopialso contend that they are entitled to prejudgment interest, ifthey succeed on their claim for owelty.In the cross-appeal, the Navajo assert that the Hopi shouldbe judicially estopped from seeking owelty. Moreover, theNavajo want an owelty payment from the Hopi, and arguethat the Hopi got the better land. We hold that the districtcourt erred in its interpretation of the statute and remand fora determination of the amount of owelty due the Hopi. Weaffirm the district court's denial of owelty to the Navajo. Wefurther hold that the Hopi are not judicially estopped fromseeking owelty, and that they must receive prejudgment inter-est on it.B. ImprovementsThe principal legal contention we must resolve is theHopi's argument that the district court misconstrued the statu-tory language directing that the value of the partitioned land"shall be based on not less than its value with improvementsand its grazing capacity fully restored." S 640d-5(d). The dis-trict court determined the land's worth with its grazing capac-ity fully restored and with only those improvements that, asdescribed by the district court, were necessary to restore thegrazing potential to the maximum extent feasible. Presum-ably, the district court was referring to improvements such asroads, stream diversions, irrigation canals, and fences, whichcan help improve the land's grazing capacity.On appeal, the Hopi assert that the district court wronglyinterpreted the plain language of the statute calling for the val-uation of "improvements." The Hopi argue that the districtcourt should have valued all improvements, including hospi-tals, schools, churches, hogans, trading posts and other struc-tures. The Hopi contend that these improvements allcontribute to the value of the land as an Indian reservation. Attrial, the Hopi expert agreed that the land should be appraisedas an Indian reservation, with potential for, inter alia,agriculture, grazing, rural residential habitation and limitedcommercial enterprise. The Navajo's competing expert tookthe view that the land should be valued strictly as a cattleranching operation and that most buildings were of no signifi-cance.[12] The legislative history does little to answer the ques-tion of whose valuation is correct, as it refers to improve-ments without ever giving any indication of what type ofimprovements Congress contemplated. See, e.g., H.R. Rep.No. 909, 93rd Cong., 2d Sess. (1974); S. Rep. No. 1177, 93rdCong. 2d Sess. (1974). Thus, we focus on the statute itself.The Navajo's valuation appears to do violence to the statutorylanguage, for it ignores the Congressional directive to value"improvements." The district court's view that"improvements" should be limited to those necessary torestore the land to full grazing capacity also finds no supportin the statute. Indeed, the statute's conjunctive structure sug-gests that an independent value should be assessed for"improvements" and for the land fully restored. Moreover,Congress did not qualify the word "improvements; " the stat-ute contains no express limitation on the type of improve-ments that can comprise the value of the partitioned land, orthe purpose that the improvements must serve before they canbe included in value.[13] Nevertheless, we cannot add the full value of thebuildings on the NPL to the value of the Navajo land, sincemost of the structures on the NPL are privately owned and arenot part of the real property that was given to the NavajoNation at partition. For example, the residences, primarilyhogans or smaller structures, are owned and were paid for byindividual Navajo. The same is true of the barns, sheds andcorrals on the NPL. Moreover, even if these structures werenot privately owned, they likely would have no appreciablevalue for owelty purposes, as the Hopi expert testified that theHopi routinely demolish such structures once the Navajo haveabandoned them.The buildings on the NPL that have the most significantintrinsic value include schools and hospitals that belong to theUnited States and which, like the private residences, cannotbe added directly to the value of the NPL because they werenot partitioned to the Navajo. The same logic applies tochurches and missions on the NPL, which are owned andmanaged by their respective religious organizations, and tostructures erected on the NPL by third party entrepreneurs,such as the Peabody coal mining operation.[14] The Hopi therefore alternatively contend that the dis-trict court should not value the improvements themselves, butrather the land's enhanced value because those improvementsare on it. We believe this is the only interpretation of the stat-ute that gives meaning to all of its terms and the one that bestaccords with Congressional intent. The district court con-cluded that "there is no competent evidence that the NPL hadmore improvements than the HPL which were necessary torestore the partitioned lands" because it had first (erroneously)interpreted what "improvements" means. Consequently, thedistrict court made no findings of fact regarding the contribut-ing value of such things as schools, churches, and hospitals,to the value of the JUA. Nor did the court evaluate the meth-odology underlying the competing expert opinions about suchcontributing value. For this reason, we remand to the districtcourt so that, guided by the correct interpretation of"improvements," it may consider and evaluate the conflictingexpert opinions, and decide what owelty payment, if any, isdue the Hopi based on the contributing value of all improve-ments.C. Grazing capacityFinally, we turn to the Navajo's Rule 59(e) motion, essen-tially a request for owelty, which the district court denied. TheNavajo argue that because the district court accepted the opin-ion of an expert who opined that the HPL fully restored wouldsupport more grazing than the NPL fully restored, the districtcourt was obligated to award the Navajo owelty relief. Thedistrict court, however, correctly noted in accepting that opin-ion that the same expert also testified to a 10 to 15 percentmargin of error in his restored grazing capacity figures. Anydifference between the HPL and the NPL was within thatmargin of error, and hence not statistically relevant. The dis-trict court did not err in denying the Rule 59(e) motion.D. Judicial EstoppelThe doctrine of judicial estoppel bars a party from takinginconsistent positions in the same litigation. Morris v. State ofCal., 966 F.2d 448, 452 (9th Cir. 1991), cert. denied, 506 U.S.831 (1992). The Navajo argue that the Hopi should be judi-cially estopped from seeking owelty because, prior to parti-tion, the Hopi represented to the district court that thepartition would not result in an owelty payment. We agreewith the district court that this argument should be rejectedbecause no court ever adopted the original Hopi position thatthe partition would not result in an owelty payment. SeeMigard Tempering, Inc. v. Selas Corp., 902 F.2d 703 (9th Cir.1990) (court must adopt position for judicial estoppel toapply).E. Prejudgment interestOur decision here is controlled by Hopi Tribe, 46 F.3d 908.There, we held that S 640d-17(e) of the Settlement Act, whichallows the Hopi and the Navajo to sue one another for all rem-edies available in federal district court, allows for recovery ofprejudgment interest. Although that decision was reached inthe context of a suit for fair rental value of post partition useof the HPL by the Navajo, its logic applies with equal forcein this context. Thus, we hold that the Hopi are entitled to pre-judgment interest.F. ConclusionWe therefore reverse the district court's denial of oweltyand remand so that the Hopi may seek compensation for anydisparity in value and prejudgment interest thereon. In allother respects, we affirm the district court's valuation ofowelty.IV. THE DAMAGES CASE, Appeals Nos. 94-17032,95-15029A. BackgroundIn the action giving rise to these appeals, the Hopi sued theNavajo and the United States to recover for damages to theHPL caused by Navajo overgrazing prior to the 1979 parti-tion. The district court held that while the conduct creatingliability occurred before the 1979 partition, the Hopi's com-pensation would be measured by the value of the lost grazingopportunity that the Hopi suffered after partition. In otherwords, the Hopi could recover the post-partition difference invalue between the land "as is" and the land fully restored.None of the parties contest this ruling on appeal.[15] After trial, the district court awarded the Hopi$3,167,388.84 in damages against the Navajo, and absolvedthe United States of liability on the ground that the govern-ment made reasonable efforts to protect the range. Both theHopi and the Navajo challenge the district court's calcula-tions. Their contentions lack merit, except for the Hopi com-plaint that the district court wrongly denied damages for lostgrazing opportunity on lands that the Hopi set aside for wild-life. Accordingly, we remand so the district court can add thevalue of that lost opportunity to the damages award. Further,the Navajo argue that the United States should be held liablefor its failure to adequately protect the range. We agree withthe district court's application of a reasonableness standardand affirm the district court's denial of liability on the basisof factual findings that are not challenged as clearly errone-ous.B. Calculation of damagesWe turn first to the contentions concerning the districtcourt's calculation of damages. The court computed the lostgrazing opportunity using the following method. First, it esti-mated the fully restored annual grazing capacity of the HPL,finding that the HPL could be restored to excellent condition,but maintained as grazing land at only 75% of that condition.The Hopi challenge this finding on appeal. Second, the courtdetermined that the HPL would be fully restored by 1995.Third, it estimated the total lost grazing capacity by calculat-ing the difference between the fully restored grazing capacityand the actual annual grazing capacity for each year between1979 and 1995, and then adding up the lost opportunity foreach of these years. Fourth, it put a price on the lost grazingopportunity by referring, as in the use case, to adjusted privateArizona lease rates instead of federal lease rates. Finally, thecourt discounted the future damages to their present value.These three steps are not challenged.When estimating the total lost grazing capacity, the courtmade several adjustments that the Hopi challenge here. Itdecreased its estimate of the lost grazing opportunity by mak-ing "management cuts" to account for the Hopi practice ofgrazing cattle instead of sheep. Sheep typically graze all avail-able forage. Cattle, by contrast, do not spontaneously grazehard-to-reach forage, prefer certain kinds of terrain over oth-ers, and tend to congregate within one-and-a-half miles ofwater sources. Because cattle use less acreage, reasoned thedistrict court when making the cuts, the Hopi lost less grazingopportunity than they would have if they grazed sheep. Inaddition, the court excluded the lost opportunity associatedwith seven range units that the Hopi reserved for wildliferather than livestock; we refer to these exclusions as the"vacant range cuts."The district court also made an adjustment that the Navajochallenge on appeal: it increased its estimate of lost grazingto account for the eventual completion of water developmentprograms on the HPL. Completion of these projects increasesthe acreage accessible to cattle, thereby increasing the Hopi'slost opportunity.[16] We address the Hopi challenges first. The Hopi arguethat the district court clearly erred in setting potential grazingcapacity at 75%, rather than 100%, of excellent condition.However, several experts, including the Hopi's own, testifiedthat the range could not be grazed at 100% of excellent condi-tion. The court's finding was not clearly erroneous.The Hopi also challenge the district court's managementand vacant range cuts, arguing that the value of the lost graz-ing opportunity should be premised on the Hopi's right oropportunity to use the land, rather than how the Hopi actuallyused the land. They contend that the management cuts wereinappropriate because they could have fully utilized theHPL's grazing capacity by raising sheep instead of cattle. Fur-ther, they contend that the vacant range cuts were inappropri-ate because they could have used their seven vacant rangeunits for grazing, but chose to leave that land fallow in orderto accelerate the restoration process. The Navajo and the gov-ernment respond that damages should be limited to realopportunity costs, which are tied to the Hopi's actual use ofthe land.[17] The Restatement (Second) of TortsS 929, concerningHarm to Land from Past Invasions, provides the most relevantauthority. It states that "[i]f one is entitled to judgment forharm to land resulting from past invasion . . ., the damagesinclude compensation for . . . the loss of use of the land . . . ."Comment d to S 929 explains that "the plaintiff is entitled torecover for the past or prospective loss of use . . . as stated inS 931." (emphasis added). Comment b toS 931 provides: The owner of the subject matter is entitled to recover as damages for the loss of the value of the use, at least the rental value of the . . . land during the period of deprivation. This is true even though the owner in fact has suffered no harm through the deprivation, as when he was not using the subject matter at the time . . . . The use to which . . . the land is commonly put . . . [is] to be taken into consider- ation as far as [it] bear[s] upon the value of the use to the owner or the rental value.Restatement (Second) of Torts S 931 cmt. b (emphasisadded). Thus, under the Restatement the value of the lostgrazing opportunity turns on the type of use to which the landwas "commonly put." The record reveals that the Hopi have"commonly put" the HPL to use for grazing cattle, rather thansheep. The district court made the management cuts toexclude forage that was inaccessible to cattle. This was inaccordance with the Restatement principle. We affirm the dis-trict court's management cuts.[18] Our result differs with respect to the vacant range cuts.Unlike the acreage excluded by the management cuts, the landexcluded under the vacant range cuts was accessible to cattle.Thus, the question is whether the Hopi should be awarded lostopportunity damages for land that could have been put to itscommon use, but which the Hopi chose not to use in the cus-tomary manner. We hold that the Hopi should be awardeddamages for lost grazing opportunity on the vacant ranges. Asthe Restatement explains, an owner can suffer deprivationeven if the owner "was not using the subject matter at thetime." Id. We therefore reverse the district court's vacantrange exclusion and remand for inclusion of the lost grazingopportunity on the vacant range units in the Hopi's damagesaward.The Navajo argue that the upward adjustment for the futurecompletion of water development programs constituted clearerror because such programs will have no impact on Hopigrazing. They contend that the programs are saddled withinadequate funding and resistance from the Hopi themselves,preventing their development. However, the Navajo's ownexpert testified that these programs had made substantialprogress, and the Hopi's expert recommended the upwardadjustment. The court did not clearly err in following that rec-ommendation.[19] The Navajo also argue that the damages award wasexcessive. The Navajo and the Hopi both agree that the dam-ages award, coupled with the post-partition rent, should equalthe fully restored value of the HPL. In other words, they agreethat the value of the HPL fully restored is equal to lost grazingopportunity (damages) plus available grazing opportunity(rent). The Navajo point out, however, that the payment theymade in the rent case, Hopi Tribe, 46 F.3d 908, plus the dam-ages award here, adds up to more than the worth of the fullyrestored HPL. From this the Navajo conclude that the dam-ages award is excessive. The Navajo's argument is withoutmerit. The rent award included considerations unrelated toactual grazing, such as financial penalties for trespassing live-stock. These penalties and other factors unrelated to grazing,rather than an excessive damages award, are what cause theappearance of overcompensation. The district court did notclearly err in finding that the damages award was not exces-sive.Finally, the Navajo challenge the testimony of expert JohnWorkman, contending, as they did in the use case, that he isnot qualified. See supra II.C. We reject their contention forthe same reasons articulated in part II.C. Id. C. Federal Government LiabilityFinally, we address the question of the United States' liabil-ity. We must decide whether the United States should bearany fiscal responsibility for the tragedy of these commons.The district court held that if the United States negligentlyfailed to protect the JUA, the United States, together with theNavajo, would be jointly and severally liable for damages tothe land. The district court concluded that the government wasnot negligent, stating that the Hopis failed to sustain their bur-den to show "that the damage to the HPL was caused byunreasonable government action or inaction."The Hopi appealed that judgment, arguing that the districtcourt erred by using negligence, rather than strict liability, asthe standard for government liability. After oral argument inthese appeals, the United States settled with the Hopi for$2,400,000, and the Hopi moved to abandon the portion oftheir appeal contesting the decision in favor of the govern-ment. We granted that motion, but allowed the Navajo to relyon the arguments in the Hopi briefs with regard to joint liabil-ity. Additionally, the Navajo contend that the United Statesshould be exclusively liable.[20] We agree with the district court that the government'sbehavior should be evaluated using reasonableness as theyardstick. The district court assessed government liability inaccordance with the only available provision addressing dam-ages to the land, S 640d-5(d).4 That section provides that thegovernment will be liable for damages to the land if the gov-ernment fails "to provide protection where such protection isor was required by law or by the demands of the trustrelationship." Protections required by law are coterminouswith those required by the trust relationship. See United Statesv. Mitchell,
463 U.S. 206, 224
, 103 S.Ct. 2972 (1983) (statu-tory and regulatory provisions define contours of federal gov-ernment's trust obligations when it assumes responsibility asa trustee for Indian lands); accord 25 C.F.R. 153.3 (1976)(regulations are promulgated to "carry out the Secretary'strust responsibility" over the JUA). Since the government'sliability is predicated on trust obligations, it need take thoseprotective measures that a reasonable or prudent trustee wouldtake. Navajo Tribe v. United States, 9th Cir. 336, 400 (1986);Restatement, (Second) Trusts, S 176.[21] The district court may well have erred in describingthe appropriate standard as a negligence, or reasonable personstandard, rather than a fiduciary, or reasonable trustee stan-dard, but the Hopi have not argued that the district court mea-sured the government's fault by the wrong standard. Rather,the Hopi ask that the government be held strictly liable, with-out regard to fault. We therefore hold that the district courtdid nor err in determining the government's liability using thereasonableness standard rather than a standard of strict liabil-ity. The Hopi do not challenge the findings as clearly errone-ous.CONCLUSIONWe affirm the entire judgment of the district court in theuse case. In the owelty case, we remand so that the districtcourt may determine the amount of owelty, if any, due theHopi based on the value of the land and the contributing valueof improvements, and affirm in all other respects. In the dam-ages case, we reverse the district court's decision not to creditthe Hopi for lost opportunity on the seven vacant range unitsset aside for wildlife, but otherwise affirm the judgment.AFFIRMED in part, REVERSED and REMANDED inpart. Each party shall bear its own costs on appeal.
_____________________________FLETCHER, Circuit Judge: Partial Concurrence and PartialDissentI concur substantially in the majority's opinion.I respectfully dissent, however, from the majority's refusalto reverse the district court's holding that the United States isnot liable for failure to protect the HPL from overgrazingprior to partition in 1979.The majority concludes as do I that the district courtapplied the wrong standard in assessing the government's lia-bility. The district court held the government to a negligencestandard, holding the Hopi responsible for proof that "thedamage to the HPL was caused by unreasonable governmentaction or inaction," rather than to the duty of a reasonabletrustee, who is under an affirmative duty "to the beneficiaryto use reasonable care and skill to preserve the trustproperty." (Restatement (Second), Trusts,S 176(1959))(emphasis added).The government's obligation as trustee required it to takethose protective measures that would have prevented the spo-liation of the trust land by overgrazing--the very conduct bythe Navajo that proper oversight by the government shouldhave prevented. The government as trustee had affirmativeduties of oversight--an obligation to investigate and to beinformed and to act affirmatively to assure the protection ofthe grazing land--a fragile ecosystem--from overgrazing.The government's obligation, in short, was to prevent theNavajo from doing the very acts that imposed liability on theNavajo.My disagreement stems from the majority's conclusion thatdespite the district court's error, its holding should standbecause the Hopi have not challenged on appeal the districtcourt's finding that the government acted reasonably.1 Butthat finding of reasonableness was in the context of the inap-propriate negligence standard--what is reasonable conductfor a non-fiduciary is not necessarily reasonable conduct fora trustee since the trustee has an affirmative duty to protectand preserve the trust res. That is the very point the Hopimake: they assert that the government breached its fiduciaryduty to protect the HPL from overgrazing. They offer theproof of the breach in the condition of the land, a conditiondirectly traceable to the overgrazing."Reasonableness" as a standard is only meaningful whendefined in context; a "reasonable" trustee must clearly domore than a "reasonable" person would to prevent thedestruction of trust property.I would therefore remand to the district court so that itcould determine the government's liability by properly apply-ing the reasonableness standard to which a trustee is held.Since the Hopi did not challenge the factual findings below asclearly erroneous, whether the government fulfilled its obliga-tions as trustee should be determined in light of those find-ings.I do not ignore the fact that the relationship of the UnitedStates to the Navajo and the Hopi is unique. It owes trustduties to each; if it failed in its duties, its failures were to both(failure to protect the trust property to the detriment of theland and to both the Hopi and the Navajo; failure to overseeand impose proper controls on the grazing practices of theNavajo).Upon remand, I would require the district court to deter-mine and assess the government's liability and fiscal obliga-tions and determine the effect, if any, on the amount owed tothe Hopi by the Navajo.Accordingly, I dissent. the end
___________________________FOOTNOTES 1 See, e.g., Emily Benedek, The Wind Won't Know Me: A History of theNavajo-Hopi Land Dispute (1992); Jerry Kammer, The Second LongWalk: The Navajo-Hopi Land Dispute (1980); Charles Miller, The NavajoHopi Relocation and the First Amendment Free Exercise Clause, 23U.C.S.F. L. Rev. 97 (Fall, 1988); Healing v. Jones, 210 F.Supp. 125, 129n.1 (D. Ariz. 1962), aff'd,
373 U.S. 758
(1963); Hopi Tribe v. NavajoTribe, 46 F.3d 908 (9th Cir.), cert. denied, 116 S.Ct. 337 (1995); Hamiltonv. MacDonald, 503 F.2d 1138 (9th Cir. 1974).2 S 640d-17. Actions for accounting, fair value of grazing, and claims fordamages to land (a) Authorization to commence and defend actions in District CourtEither tribe, acting through the chairman of its tribal council, for and onbehalf of the tribe, including all villages, clans, and individual membersthereof, is hereby authorized to commence or defend in the District Courtan action or actions against the other tribe for the following purposes ifsuch action or actions are not settled pursuant to section 640d-2 or 640d-3 of this title: . . . (2) for the determination and recovery of the fair value of the grazing and agricultural use by either tribe and its individual members since the 28th day of September 1962 of the undivided one-half interest of the other tribe in the lands within the joint use area, together with interest at the rate of 6 per centum per annum compounded annually, notwithstanding the fact that the tribes are tenants in common of such lands . . .3 Section 640d-5(d) of the Settlement Act provides:In any partition of the surface rights to the joint use area, the lands shall,insofar as is practicable, be equal in acreage and quality: Provided, Thatif such partition results in a lesser amount of acreage, or value, or both toone tribe such differential shall be fully and finally compensable to suchtribe by the other tribe. The value of the land for the 18 purposes of thissubsection shall be based on not less than its value with improvements andits grazing capacity fully restored: Provided further, That, in the determi-nation of compensation for any such differential, the Federal Governmentshall pay any difference between the value of the particular land involvedin its existing state and the value of such land in a fully restored statewhich results from damage to the land which the District Court findsattributable to a failure of the Federal Government to provide protectionwhere such protection is or was required by law or by the demands of thetrust relationship.4 Section 640d-5(d) is an owelty provision. However, it also discussesthe government's liability for the difference in value between the land "asis" at the time of partition and the land fully restored. That is, 640d-5(d)covers damages as well as owelty. The parties on appeal do not disputethe district court's reliance on this section.1 After oral argument in these appeals, the United States settled with theHopi for $2,400,000, and the Hopi moved to abandon this portion of theirappeal. We granted that motion, but allowed the Navajo to rely on theHopi's arguments with regard to joint liability.