FILED

United States Court of Appeals

Tenth Circuit

February 22, 2017

Elisabeth A. Shumaker

Clerk of Court

PUBLISH

UNITED STATES COURT OF APPEALS

TENTH CIRCUIT

STATE OF WYOMING, and

WYOMING FARM BUREAU

FEDERATION

Petitioners,

v. Nos. 14-9512 and 14-9514

UNITED STATES ENVIRONMENTAL

PROTECTION AGENCY; E. SCOTT

PRUITT, in his official capacity as

Administrator of the United States

Environmental Protection Agency; DEB

THOMAS, in her official capacity as

Acting Region 8 Administrator of the

United States Environmental Protection

Agency,*

Respondents.

---------------------------------------------

THE NORTHERN ARAPAHO TRIBE;

EASTERN SHOSHONE TRIBE; CITY OF

RIVERTON, WYOMING; FREMONT

COUNTY, WYOMING, 

Intervenors.

*

 Pursuant to Fed. R. App. P. 43(c)(2) E. Scott Pruitt is substituted for

Gina McCarthy as the Administrator of the United States Environmental

Protection Agency, and Deb Thomas is substituted for Shaun McGrath as the

Acting Region 8 Administrator of the United States Environmental Protection

Agency.
---------------------------------------------

STATE OF IDAHO; STATE OF

ALABAMA; STATE OF COLORADO;

STATE OF KANSAS; STATE OF

MONTANA; STATE OF NEBRASKA;

STATE OF NORTH DAKOTA; STATE OF

OKLAHOMA; STATE OF SOUTH

DAKOTA; STATE OF UTAH; INDIAN

LAW PROFESSORS; RIVERTON

MEMORIAL HOSPITAL, LLC, 

Amici Curiae. 

PETITION FOR REVIEW OF A FINAL ORDER FROM THE 

ENVIRONMENTAL PROTECTION AGENCY

(NO. EPA-1-R08-2013-0007)

Michael McGrady (Peter K. Michael, Wyoming Attorney General, Jay Jerde and

James Kaste with him on the briefs), Office of the Attorney General for the State

of Wyoming, Cheyenne, Wyoming, for Petitioner State of Wyoming. 

Gina Cannan (Steven J. Lechner with her on the briefs), Mountain States Legal

Foundation, Lakewood, Colorado, for Petitioner Wyoming Farm Bureau

Federation.

Samuel C. Alexander, Chief, Indian Resources Section (John C. Cruden, Assistant

Attorney General, Washington, D.C., and David A. Carson, Environmental

Defense Section, Denver, Colorado, with him on the briefs) Environment and

Natural Resources Division, United States Department of Justice, Washington,

D.C., for Respondents.

Kelly A. Rudd (Andrew W. Baldwin, Berthenia S. Crocker, and Janet E. Millard

with him on the briefs) Baldwin, Crocker & Rudd, Lander, Wyoming, for

Intervenor Northern Arapaho Tribe.

Donald R. Wharton (Robert Hitchcock, Eastern Shoshone Tribe, Office of the

Attorney General, Fort Washakie, Wyoming, with him on the briefs), Native

American Rights Fund, Boulder, Colorado, for Intervenor Eastern Shoshone

Tribe.

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Jodi A. Darrough, Deputy Fremont County Attorney, and Rick L. Sollars, City

Attorney, City of Riverton, Wyoming, on the briefs for Intervenors Fremont

County and City of Riverton, Wyoming.

Lawrence G. Wasden, Attorney General, Steven L. Olsen, Chief of Civil

Litigation, and Clay R. Smith, Deputy Attorney General, Boise, Idaho, Luther

Strange, Attorney General, Montgomery, Alabama, John Suthers, Attorney

General, Denver, Colorado, Derek Schmidt, Attorney General, Topeka, Kansas;

Tim Fox, Attorney General, Helena, Montana, Jon Bruning, Attorney General,

Lincoln, Nebraska; Wayne Stenehjem, Attorney General, Bismark, North Dakota, 

E. Scott Pruitt, Attorney General, Oklahoma City, Oklahoma, Marty Jackley,

Attorney General, Pierre, South Dakota, and Sean D. Reyes, Attorney General,

Salt Lake City, Utah, on the brief for Amici Curiae States of Idaho, Alabama,

Colorado, Kansas, Montana, Nebraska, North Dakota, Oklahoma, South Dakota,

and Utah.

Colette Routel, William Mitchell College of Law, Saint Paul, Minnesota, Bethany

Berger, University of Connecticut School of Law, Hartford, Connecticut, and

Sarah Wheelock, Tilden McCoy + Dilweg LLP, Sioux City, Iowa, on the brief for

Amici Curiae Indian Law Professors.

Kevin J. Kuhn, LaMar F. Jost, and H. Camille Papini-Chapla, Wheeler Trigg

O’Donnell LLP, Denver, Colorado, and Patrick J. Murphy, Williams, Porter, Day

& Neville, P.C., Casper, Wyoming, on the brief for Amicus Curiae Riverton

Memorial Hospital, LLC.

Before TYMKOVICH, Chief Judge, KELLY, and LUCERO, Circuit Judges.

TYMKOVICH, Chief Judge.

This case requires us to determine whether Congress diminished the

boundaries of the Wind River Reservation in Wyoming in l905. We find that it

did.

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The Eastern Shoshone and Northern Arapaho Tribes jointly inhabit the

Wind River Reservation. The State of Wyoming and the Wyoming Farm Bureau

Federation challenge a decision by the Environmental Protection Agency granting

the Tribes’ application for joint authority to administer certain non-regulatory

programs under the Clean Air Act on the Reservation. As part of their application

for administrative authority, the Tribes were required to show they possess

jurisdiction over the relevant land. In their application, the Tribes described the

boundaries of the Wind River Reservation and asserted that most of the land

within the original 1868 boundaries fell within their jurisdiction. 

Wyoming and others submitted comments to the EPA arguing the

Reservation had been diminished in 1905 by act of Congress, and that some land

described in the application was no longer within tribal jurisdiction. After

review, the EPA determined the Reservation had not been diminished in 1905 and

the Tribes retained jurisdiction over the land at issue. Because the EPA decided

the Tribes otherwise satisfied Clean Air Act program requirements, it granted

their application. 

Wyoming and the Farm Bureau appealed the EPA’s Reservation boundary

determination. Regionally applicable final actions of the EPA are directly

appealable to this court. Exercising jurisdiction under 42 U.S.C. § 7607(b)(1), we

grant the petition for review, vacate the EPA’s boundary determination, and

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remand for further proceedings consistent with this opinion. We find by its 1905

legislation, Congress evinced a clear intent to diminish the Reservation. 

I. Background

The history of federal Indian policy in the United States is marked by a

series of eras, each characterized by a different approach to the inevitable conflict

between the Native Americans who inhabited western America and homesteaders

flooding west in search of a better life. Cohen’s Handbook of Federal Indian Law

7–8 (Nell Jessup Newton et al. eds., 2012). The story of the Wind River

Reservation begins in the second half of the nineteenth century, when a new

federal policy of allotment and assimilation began to take shape, which followed

a period when Indian reservations were created throughout the western United

States. Unsurprisingly, westward expansion placed pressures on the traditional

lifestyles of the Native American tribes. Recognizing the potential for conflicts,

particularly over land, the United States negotiated a series of treaties and

agreements with dozens of tribes, including the Eastern Shoshone. 

The Eastern Shoshone are part of the larger Shoshone Tribe, who in the

mid-nineteenth century inhabited what would become the states of Colorado,

Idaho, Nevada, Utah, and Wyoming. Henry Stamm, People of the Wind River 9

(1999). In 1863, the United States and the Eastern Shoshone entered into the

First Treaty of Fort Bridger, 18 Stat. 685 (1863), which established “Shoshonee

County,” an area encompassing more than forty-four million acres. See United

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States v. Shoshone Tribe of Indians of Wind River Reservation of Wyo., 304 U.S.

111, 113 (1938). But the treaty proved to be short lived. With the end of the

Civil War, a new wave of settlers forged westward. Fearing the Eastern

Shoshone’s homeland would be settled and thus lost forever, the tribal leader,

Chief Washakie, urged the United States to reserve the Wind River Valley—the

Tribe’s historic buffalo hunting grounds—as the Eastern Shoshone’s permanent

homeland. 

Chief Washakie’s efforts were successful: in 1868, the United States and

the Eastern Shoshone Tribe signed the Second Treaty of Fort Bridger, 15 Stat.

673 (1868). This treaty set aside roughly three million acres for exclusive tribal

use. In exchange, the Tribe relinquished its claim to the land held under the 1863

treaty. Shoshone, 304 U.S. at 113. As it had promised, the United States

developed the Reservation’s infrastructure and began to establish and expand

agricultural lands in an effort to aid the Eastern Shoshone’s transition away from

hunting wild game, which was rapidly disappearing. For their part, the Eastern

Shoshone resolved to settle permanently on the Reservation, pursue an agrarian

lifestyle, and send their children to school. But land issues persisted: settlers vied

for agricultural lands south of the Big Wind River, and the Reservation’s

superintendent feared it would be impossible to observe the boundaries created by

the 1868 treaty. 

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Meanwhile, Congress had departed from its previous policy of segregating

tribes from homesteaders in favor of a new policy of educating Native American

children in residential boarding schools and splitting up communal, tribally

owned reservations into individual, privately owned parcels of land. Judith V.

Royster, The Legacy of Allotment, 27 Ariz. St. L.J. 1, 7–9 (1995). At the time,

Congress, and indeed most of America, assumed the reservation system would

eventually cease to exist and members of Native American tribes would become

fully assimilated into American society. See Solem v. Bartlett, 465 U.S. 463, 468

(1984); Marta Adams et al., American Indian Law Deskbook 93 (2015). Thus,

reservations began to shrink in size. In 1874, the Eastern Shoshone Tribe sold all

of its land south of the forty-third parallel in the so-called Lander Purchase in

exchange for a payment of $25,000. 18 Stat. 291, 292 (1874). According to the

ratifying act, this transaction “change[d] the southern limit of said reservation.” 

18 Stat. at 292. Around this time, the Northern Arapaho—traditionally, an enemy

of the Eastern Shoshone—joined the Eastern Shoshone on the Wind River

Reservation, where they remain today. 1877 Comm’r Indian Aff. Ann. Rep. 19.

The Wind River Reservation boundaries changed again in 1897, when

Congress passed legislation purchasing additional land. That act, known as the

Thermopolis Purchase, provided that, in exchange for $60,000, the Tribes agreed

to “cede, convey, transfer, relinquish, and surrender forever and absolutely all

their right, title, and interest of every kind and character” in a tract around the Big

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Horn Hot Springs, located on the northern boundary of the Reservation. 30 Stat.

93, 94 (1897). Following up on failed efforts to acquire additional land from the

Tribes in 1891 and 1893, in 1904 Representative Frank Mondell of Wyoming

introduced a bill initiating the cession of the land north of the Big Wind River

flowing through the north-central portion of the Reservation. The 1904

legislation was the framework for negotiations with the Tribes, which the Tribes

ultimately agreed to as amended. Congress passed the 1904 agreement in 1905. 

33 Stat. 1016 (1905). It is the 1905 Act that is at issue in this case. 

 But the 1905 Act was not the last piece of legislation affecting the

Reservation. In 1934, Congress enacted the Indian Reorganization Act, the first

step in its new national policy of tribal self-determination. See 48 Stat. 984

(1934). Since the Tribes voted to exclude themselves from this Act, however,

Congress had to pass specific legislation to carry out its new policies on the Wind

River Reservation. Thus, in 1939, Congress directed the Secretary of the Interior

to restore to tribal ownership any unsold lands in the area that had been ceded in

1905. 53 Stat. 1128, 1129 (1939).

That brings us to the present day. Currently, approximately seventy-five

percent of the land affected by the 1905 Act is held in trust by the United States

for the Tribes and their members. In 2008, the Tribes applied to the EPA for

authority to manage certain non-regulatory programs for air quality in areas under

tribal jurisdiction. They were able to do so because in 1990, Congress amended

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the Clean Air Act, 42 U.S.C. §§ 7401–671 (CAA), to authorize the EPA to treat

Native American tribes as states for the purposes of the CAA. § 7601(d). 

Pursuant to this grant of authority, the EPA promulgated the Tribal Authority

Rule, 40 C.F.R. 49, under which qualified tribes may apply for authority to

implement and manage programs for air quality in areas under tribal jurisdiction. 

42 U.S.C. § 7601(d)(2)(B).

A successful application must describe the area over which a tribe seeks to

assert its regulatory authority. Thus, in their application, the Tribes had to

specify the proposed scope of their regulatory jurisdiction, which required them

to clearly delineate the boundaries of the Reservation. The Tribes claimed the

boundaries of the Wind River Reservation were those set forth in the 1868 treaty,

reduced only by the Lander and Thermopolis transactions. As required by the

CAA, the EPA notified all governmental entities located contiguous to the

Reservation and provided local government and the general public notice and an

opportunity to comment on the proposed boundary description. When a

treatment-as-a-state application is subject to an objection, EPA may also request

additional information or consult with the Department of the Interior. 40 C.F.R.

§ 49.9(d).

In their comments, Wyoming and the Farm Bureau argued the Reservation

was diminished by the 1905 Act, which, they contended, established the current

boundaries of the Reservation. Based on these objections, the EPA asked the

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Department of the Interior for an analysis of the competing claims. In 2011, the

solicitor issued a legal opinion concluding the 1905 Act had not changed the

boundaries established by the 1868 treaty. Relying on this analysis, the EPA

issued its final decision granting the Tribes’ application. The decision agreed

with the Tribes’ interpretation that the 1905 Act did not diminish the boundaries

of the Reservation. 

II. Analysis

Our task here is limited: we must determine whether Congress diminished

the Wind River Reservation in 1905 by legislative act.1

 As we have previously

1

 We must also address two jurisdictional issues: 

(1) In response to the court’s November 17, 2015 order for supplemental

briefing regarding a mootness issue raised during oral argument, we have

reviewed the parties’ and intervenors’ supplemental briefs and find this case is

not moot. Mootness is a threshold requirement: without the existence of a live

case or controversy, we cannot constitutionally exercise jurisdiction over a claim. 

Rio Grande Silvery Minnow v. Bureau of Reclamation, 601 F.3d 1096, 1110 (10th

Cir. 2010). For a live controversy to exist, a present determination of the issues

must have “some effect in the real world,” and the parties must retain a concrete

interest in the outcome of the litigation. Id. at 1109–10. Here, even though the

EPA has revoked the Tribes’ funding under the CAA, the EPA’s determination of

the Reservation boundaries still stands, and the EPA has not indicated it will

reconsider its decision. Because the boundary determination affects the present

and future rights and responsibilities of the parties, the case is not moot.

(2) We also find the Wyoming Farm Bureau has standing to sue on behalf

of its members. For an organization to bring suit in its representative capacity, it

must show, among other things, that “its members would otherwise have standing

to sue in their own right.” Hunt v. Wash. State Apple Advert. Comm’n, 432 U.S.

333, 343 (1977). Standing requires a concrete and particularized injury that is

(continued...)

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explained, only Congress has the power to diminish reservation boundaries, and

its intent “must be clearly expressed.” Osage Nation v. Irby, 597 F.3d 1117,

1121–22 (10th Cir. 2010). Even further, diminishment “will not be lightly

inferred.” Solem v. Bartlett, 465 U.S. 463, 470 (1984). Nevertheless, we may not

“‘ignore plain language that, viewed in historical context and given a fair

appraisal clearly runs counter to a tribe’s later claims.’” Osage Nation, 597 F.3d

at 1122 (quoting Pittsburg & Midway Coal Mining Co. v. Yazzie, 909 F.2d 1387,

1393 (10th Cir. 1990)). 

The Supreme Court has declined to infer a congressional purpose of

diminishment from the passage of every surplus land act during the allotment and

assimilation period. “Rather, it is settled law that some surplus land acts

diminished reservations, and other surplus land acts did not.” Solem, 465 U.S. at

469 (citations omitted). “The effect of any given surplus land Act depends on the

language of the Act and the circumstances underlying its passage.” Id. To

determine whether the 1905 Act had the effect of diminishing the Reservation, we

1

(...continued)

traceable to the defendant’s conduct and redressable by a favorable court

decision. Lujan v. Defenders of Wildlife, 504 U.S. 555, 560–61 (1992). In this

case, some Farm Bureau members own farms within the disputed area and face

the costs of complying with a new regulatory regime following the EPA’s

decision. We have previously recognized precisely this type of injury as

sufficiently concrete and particularized. See Hydro Res., Inc. v. EPA, 608 F.3d

1131, 1144 (10th Cir. 2010). And since the alleged injuries are clearly traceable

to the EPA’s decision and would be redressed by a reversal of that decision, Farm

Bureau members have standing to sue in their own right. Therefore, we find the

Farm Bureau has standing to sue on behalf of its members. 

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look to the well-settled approach described in Solem, where the Court outlined a

hierarchical, three-step framework to ascertain congressional intent.

First, we look to the text of the statute, because it is “[t]he most probative

evidence of congressional intent.” Id. at 470; see also Nebraska v. Parker, 136 S.

Ct. 1072, 1079 (2016) (“[W]e start with the statutory text, for ‘[t]he most

probative evidence of diminishment is, of course, the statutory language used to

open Indian lands.’” (citation omitted) (second alteration in original)). 

Second, we examine the circumstances surrounding the passage of the act,

“particularly the manner in which the transaction was negotiated with the tribes

involved and the tenor of legislative reports presented to Congress.” Solem, 465

U.S. at 471; see also Parker, 136 S. Ct. at 1079; South Dakota v. Yankton Sioux

Tribe, 522 U.S. 329, 351–52 (1998). 

Third and finally, “to a lesser extent,” we look to “the subsequent treatment

of the area in question and the pattern of settlement there.” Id. at 344; Solem, 465

U.S. at 471–72. 

In doing so, we afford no deference to the EPA’s boundary determination. 

As our precedents tell us, “‘the Supreme Court has applied, without comment, a

de novo standard of review in determining congressional intent [regarding

reservation boundary diminishment].’” Osage Nation, 597 F.3d at 1122

(alteration in original) (quoting Yazzie, 909 F.2d at 1393). Although examination

of the historical record “involves a mixed question of law and fact,” de novo

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review is appropriate “[w]here a mixed question ‘primarily involves the

consideration of legal principles.’” Id. at 1393–94 (quoting Supre v. Ricketts, 792

F.2d 958, 961 (10th Cir. 1986)). The EPA does not dispute this standard of

review, because it concedes a de novo standard is “consistent with the

[Administrative Procedure Act’s] ‘otherwise not in accordance with the law’

standard,” Aple. EPA Br. 23, which we apply to the agency action here. 

A. The Text of the 1905 Act

We begin our analysis with the 1905 Act’s operative language, for

“[s]tatutory language is the most probative evidence of congressional intent to

disestablish or diminish a reservation.” Osage Nation, 597 F.3d at 1122–23. 

“‘Explicit reference to cession or other language evidencing the present and total

surrender of all tribal interests strongly suggests that Congress meant to divest

from the reservation all unallotted opened lands.’” Id. at 1123 (quoting Solem,

465 U.S. at 470). There are no magic words of cession required to find

diminishment. Rather, the statutory language, whatever it may be, must

“establis[h] an express congressional purpose to diminish.” Hagen v. Utah, 510

U.S. 399, 411 (1994).

Here, Article I of the 1905 Act reads,

The said Indians belonging on the Shoshone or Wind River

Reservation, Wyoming, for the consideration hereinafter

named, do hereby cede, grant, and relinquish to the United

States, all right, title, and interest which they may have to

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all the lands embraced within said reservation, except the

lands within and bounded by the following lines . . . . 

33 Stat. at 1016 (emphasis added). This language of cession aligns with the type

of language the Supreme Court has called “precisely suited” to diminishment. 

Yankton Sioux, 522 U.S. at 344. Indeed, it is nearly identical to the statutory

language in cases where the Supreme Court has found a congressional purpose to

diminish a reservation in the statute’s text.

For example, in DeCoteau v. District County Court for the Tenth Judicial

District, the Court considered an act providing that the Sisseton-Wahpeton Tribe

agreed to “cede, sell, relinquish, and convey to the United States all their claim,

right, title, and interest in and to all the unallotted lands within the limits of the

reservation.” 420 U.S. 425, 445 (1975). The Court found this language was

precisely suited to a congressional purpose of terminating the Lake Traverse

Indian Reservation. Id. Similarly, in Rosebud Sioux Tribe v. Kneip, the Court

held Congress clearly evinced an intent to diminish the boundaries of the Rosebud

Sioux Reservation when it passed a series of acts affecting unallotted lands on

that reservation. 430 U.S. 584, 615 (1977). The first act, passed in 1904,

provided that the Rosebud Sioux Tribe agreed to “cede, surrender, grant, and

convey to the United States all their claim, right, title, and interest in and to” the

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unallotted portion of its reservation. Id. at 597. This too, the Court held, was

language precisely suited to diminishment. Id.2 

Two decades later, in Hagen, the Court found Congress evinced a clear

intent to diminish a reservation even when it employed less express language of

cession. The operative language of the statute at issue provided that “all the

unallotted lands within said reservation shall be restored to the public domain.” 

510 U.S. at 412. The Court held this language evidenced a congressional intent

“inconsistent with the continuation of reservation status.” Id. at 414.3

 And in

Yankton Sioux, the Court unanimously held Congress spoke with a clear purpose

of diminishment when it passed an act providing that the Yankton Sioux Tribe

would “cede, sell, relinquish, and convey to the United States all their claim,

right, title, and interest in and to all the unallotted lands within the limits of the

reservation.” 522 U.S. at 344, 351. 

2

 Although the 1907 and 1910 Acts in Rosebud merely authorized the

Secretary of the Interior “to sell or dispose of” the unallotted portions, the court

found a “continuity of intent” from the earlier 1904 Act and a 1901 agreement,

based on the circumstances surrounding the passage of the later acts. Id. at

606–13. 

3

 Citing to Hagen, the EPA argues that when the operative language does

not restore ceded lands to the public domain, diminishment is less likely. We

disagree. While the Court in Hagen found language restoring lands to the public

domain probative of congressional intent to diminish a reservation, nowhere did it

suggest the absence of public domain language cuts against diminishment—

especially where, as here, the statute’s operative language includes even stronger

language of cession than in Hagen. 

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In contrast, in cases where the Court has found a lack of clear

congressional intent to diminish, the operative language of the statutes merely

opened a reservation to settlement by non-Indians or authorized the Secretary of

the Interior to act as a “sales agent” for the Native American tribes. For example,

in Seymour v. Superintendent of Wash. State Penitentiary, the Court concluded

that an act providing “for the sale of mineral lands and for the settlement and

entry under the homestead laws of surplus lands remaining on the diminished

Colville Reservation after allotments were first made . . . did no more than open

the way for non-Indian settlers to own land on the reservation.”4

 368 U.S. 351,

354–56 (1962). Similarly, in Mattz v. Arnett, the Court held an act providing that

lands within a reservation were “subject to settlement, entry, and purchase” did

not, on its own, “recite or even suggest that Congress intended thereby to

terminate the Klamath River Reservation.” 412 U.S. 481, 495–97 (1973). 

The operative language in Solem itself was similar: the act merely

“authorized and directed” the Secretary of the Interior “to sell and dispose of all

that portion of the Cheyenne River and Standing Rock Indian reservations” within

the described boundaries. 465 U.S. at 472–73. The Court compared the language

4

 The Tenth Circuit distinguished Seymour in Ellis v. Page, stating, “It is

one thing to open an Indian Reservation to mineral exploitation, allotment to

Indians, and non-Indian homesteaders by Congressional enactment as in Seymour. 

It is quite another to agree by treaty to cede and relinquish all claim, title and

interest in the lands within the limits of a reservation.” 351 F.2d 250, 252 (10th

Cir. 1965).

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to the acts in Rosebud and DeCoteau and concluded that unlike in those cases,

“the Secretary of the Interior was simply being authorized to act as the Tribe’s

sales agent.” Id. at 473. The Court added, “Nowhere else in the Act is there

specific reference to the cession of Indian interests in the opened lands or any

change in existing reservation boundaries.” Id. at 474.5

 Likewise, just last year

in Parker, the Court held that an act stating the disputed lands would be “‘open

for settlement under such rules and regulations as [the Secretary of the Interior]

may prescribe,’” 136 S. Ct. at 1079 (alteration in original) (quoting 22 Stat. 341

(1882)), fell into the category of acts that “‘merely opened reservation land to

settlement,’” id. (quoting DeCoteau, 420 U.S. at 448).6

Plainly, the 1905 Act falls into the first line of cases: those with express

language of cession. Nevertheless, the EPA and the Tribes argue that Congress’s

5

 The Court in Solem did acknowledge that language of diminishment

present elsewhere in the act undisputedly supported the view that the reservation

had been diminished. 465 U.S. at 474–75. Without express language of cession,

however, isolated references to diminishment alone could not “carry the burden of

establishing an express congressional purpose to diminish.” Id. at 475. Here, in

addition to the express language of cession in Article I, Articles I, III, IV, VI, and

IX of the 1905 Act refer to the diminished reservation. 33 Stat. at 1016, 1017,

1018, 1020, 1022.

6

 The EPA points to a circuit case, United States v. Grey Bear, which it

argues falls outside this framework. 828 F.2d 1286 (8th Cir. 1987). That case

involved an interpretation of cession language for the Devils Lake Indian

Reservation that is similar to Rosebud, DeCoteau, and here, but unlike these

cases, the legislative history of the act was quite limited, and the subsequent

treatment of the area strongly indicated Congress did not view the act as

disestablishing the reservation. Id. at 1290–91. 

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intent remains unclear, because of the absence of words such as “sell” or

“convey” that were present in other statutes during the period. But our task is not

to divine why Congress may have chosen certain synonyms over others in this

particular Act. We believe Congress’s use of the word “cede” can only mean one

thing—a diminished reservation. A review of several dictionaries from the turn

of the twentieth century confirms that adding the words “sell” or “convey” would

not materially change the intent Congress evinced in the 1905 Act.7

 And in any

event, Article II of the 1905 Act includes the word “conveyed”: 

7

 Adding the words “convey” or “sell” to Article I would not have

materially altered Congress’s expression of its intent, since the contemporaneous

definitions of “cede,” “grant,” and “relinquish” were virtually indistinguishable

from the definitions of “convey” and “sell.” For example, at the time, “cede” was

defined as “[t]o yield or surrender, give up.” Webster’s Commonsense Dictionary

76 (J.T. Thompson ed., 1902). Likewise, “grant” was defined as “[t]o allow,

yield, concede; to bestow or confer, in answer to prayer or request; to make

conveyance of, give the possession or title of.” Webster’s Practical Dictionary

165–66 (1906). And “relinquish” was defined as “[t]o give up the possession or

occupancy of; to quit; to forsake; to abandon; to give up; to resign,” Webster’s

Commonsense Dictionary 405, or “[t]o withdraw from, leave behind; to give up,

renounce a claim to, resign, quit, forsake, abandon, forego,” Webster’s Practical

Dictionary 342. 

By way of comparison, “convey” was defined as “to transfer to another,

make over,” id. 81, and “[t]o carry; to remove; to transmit,” Webster’s

Commonsense Dictionary 105. “Sell” was defined as “[t]o give or deliver in

exchange for some equivalent; to exchange for money,” id. 438, and “[t]o transfer

to another for an equivalent; to dispose of in return for something, esp. for

money,” Webster’s Practical Dictionary 361. It is true the word “sell” could add

the notion of an exchange for money, but the Supreme Court has found a statute’s

operative language to be “precisely suited” to diminishment without the presence

of the word “sell.” See Rosebud, 430 U.S. at 597.

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In consideration of the lands ceded, granted, relinquished,

and conveyed by Article I of this agreement, the United

States stipulates and agrees to dispose of the same, as

hereinafter provided . . . .

33 Stat. at 1019–20 (emphasis added).8

The EPA and the Tribes also argue the 1905 Act does not evince a clear

congressional intent to diminish the Reservation, because it lacks unconditional

payment of sum certain compensation in conjunction with cession. The 1905 Act

does not provide for a single, lump-sum payment, but rather outlines a hybrid

payment scheme, under which different amounts derived from the proceeds of

sales of the ceded lands are allocated to specific funds. For example, the 1905

Act provides $150,000 for “the construction and extension of an irrigation system

within the diminished reservation,” $50,000 for a school fund, and $50,000 for

the purchase of livestock. 33 Stat. 1017–18. The Act also creates a general

welfare and improvement fund and appropriates $85,000 for per capita payments

of $50 each. 33 Stat. 1018, 1020–21. As we explain in more detail below, it was

8

 It is worth noting the Wyoming Supreme Court, applying Solem, held the

operative language of the 1905 Act evinced Congress’s clear intent to diminish

the Reservation. Yellowbear v. State, 174 P.3d 1270, 1282 (Wyo. 2008). 

Specifically, the court concluded the language of cession in Article I was

“indistinguishable from the language of DeCoteau.” Id. And upon review of

Yellowbear’s federal habeas petition, we concluded Yellowbear failed to present

any argument “calling into question the correctness of [the Wyoming Supreme

Court’s] decision.” Yellowbear v. Atty. Gen. of Wyo., 380 F. App’x 740, 743

(10th Cir. 2010), cert. denied sub nom., Yellowbear v. Salzburg, 562 U.S. 1228

(2011). 

-19-
thought this hybrid payment scheme would yield more revenue to the tribes, since

they would be paid from the proceeds collected from the homesteaders.

The EPA and the Tribes rely on Solem, where the Court held language of

cession combined with a sum certain payment creates “an almost insurmountable

presumption that Congress meant for the tribe’s reservation to be diminished.” 

465 U.S. at 470–71. But this presumption is not a two-way street. In Hagen, the

Court expressly rejected the argument that a finding of diminishment requires

“both explicit language of cession or other language evidencing the surrender of

tribal interests and an unconditional commitment from Congress to compensate

the Indians.” 510 U.S. at 411 (emphasis added). The Court explained, “While the

provision for definite payment can certainly provide additional evidence of

diminishment, the lack of such a provision does not lead to the contrary

conclusion.” Id. at 412. The Court continued, “In fact, the statutes at issue in

Rosebud, which we held to have effected a diminishment, did not provide for the

payment of a sum certain to the Indians.” Id. And indeed, in Rosebud, the Court

had likewise noted that a sum certain payment or lack thereof is only one of many

textual indicators of congressional intent. 430 U.S. at 598 n.20. Congress’s

decision to abandon the sum certain method of payment was “not conclusive with

respect to congressional intent.”9

 Id. at 588. What matters most is not the

9

 The Court in Rosebud added that the act at issue was not completely

devoid of a guaranteed payment. The Court observed, “[d]espite this ‘uncertain

(continued...)

-20-
mechanism of payment, but rather the “language of immediate cession.” Id. at

597.

Finally, the EPA and the Tribes argue the trusteeship language in the 1905

Act demonstrates that Congress merely meant for the United States to hold the

land in trust for the Tribes until it was sold. The Act therefore effected no change

in ownership until parcels were sold to settlers. In particular, the EPA and the

Tribes point to Article IX of the Act, which provides,

[N]othing in this agreement contained shall in any manner

bind the United States to purchase any portion of the lands

herein described or to dispose of said lands except as

provided herein, or to guarantee to find purchasers for said

lands or any portion thereof, it being the understanding

that United States shall act as trustee for said Indians to

dispose of said lands and to expend for said Indians and

pay over to them the proceeds received from the sale

thereof only as received, as herein provided.

33 Stat. at 1020–21. In support of this argument, the EPA relies on similar

language the Court considered in Ash Sheep Co. v. United States, 252 U.S. 159

(1920). But Ash Sheep is of limited utility in light of the Court’s more recent

9

(...continued)

sum’ proviso,” the act mandated that “all lands herein ceded and opened to

settlement . . . remaining undisposed of at the expiration of four years from the

taking effect of this Act, shall be sold and disposed of for cash . . . .” Rosebud,

430 U.S. at 596 n.18 (citation omitted). In the Court’s words, such arrangement

“suggests that Congress viewed this land as disestablished immediately.” Id. 

Similarly, here, the 1905 Act requires “[t]hat any lands remaining unsold eight

years after the said lands shall have been opened for entry may be sold to the

highest bidder for cash without regard to the above minimum limit of price.” 

33 Stat. at 1021. 

-21-
precedent, in which it has concluded trust status is not incongruous with

diminishment. And indeed, Ash Sheep is seldom mentioned in subsequent cases,

because it dealt with the question whether lands became “public lands”—a

question the Court has stated is “logically separate” from diminishment. See

Rosebud, 430 U.S. at 601 n.24. 

In any event, it is clear trust status can exist even if a reservation has been

diminished. In Rosebud, for example, the Court considered a series of statutes in

which the United States did not promise to find purchasers for the lands, but

rather agreed to act as trustee for the Indians to dispose of the lands and collect

and distribute the proceeds. 430 U.S. at 596, 608. The Court held congressional

intent was to diminish the Rosebud Reservation, notwithstanding the trusteeship

provisions. See id. 430 U.S. at 615. The Court agreed with the Eighth Circuit

that “‘the fact that a beneficial interest is retained does not erode the scope and

effect of the cession made, or preserve to the reservation its original size, shape,

and boundaries.’” Id. at 601 n.24 (quoting Rosebud Sioux Tribe v. Kneip, 521

F.2d 87, 102 (8th Cir. 1975)). Even the dissent acknowledged, “[o]f course, it is

possible that Congress intended to remove the opened counties from the

Reservation while leaving the Indians with a host of rights in the counties.” 

Rosebud, 430 U.S. at 622. 

In sum, the express language of cession in the 1905 Act indicates Congress

intended to diminish the boundaries of the Wind River Reservation,

-22-
notwithstanding the lack of a sum certain payment and the inclusion of a

trusteeship provision. 

B. The Historical Context of the Act

The contemporary historical context further confirms Congress intended to

diminish the Wind River Reservation when it passed the 1905 Act. Although we

believe the plain statutory language is precisely suited to diminishment, we also

consider “the manner in which the transaction was negotiated with the tribes

involved and the tenor of legislative reports presented to Congress.” Solem, 465

U.S. at 471; see also Yankton Sioux, 522 U.S. at 351. As the Supreme Court has

stated, “[e]ven in the absence of a clear expression of congressional purpose in

the text of a surplus land Act, unequivocal evidence derived from the surrounding

circumstances may support the conclusion that a reservation has been

diminished.” Id. Of course, here, we need not search for unequivocal evidence,

for the statutory language evinces a congressional intent of diminishment. But

our scrutiny of the circumstances surrounding the 1905 Act confirms Congress

indeed intended to diminish the Reservation’s boundaries. 

The legislative history and the negotiations leading up to the 1905 Act

reveal Congress’s longstanding desire to sever from the Wind River Reservation

the area north of the Big Wind River. As in Rosebud, “[a]n examination of the

legislative processes which resulted in the 190[5] Act convinces us . . . that this

purpose was carried forth and enacted.” 430 U.S. at 592. “Because of the history

-23-
of the . . . Agreement, the 190[5] Act cannot, and should not, be read as if it were

the first time Congress had addressed itself to the diminution of the [Wind River]

Reservation.” See id.

In 1891, Congress drafted a bill that, had it passed, would have changed the

Reservation’s boundaries to exclude the land north of the Big Wind River. Under

the 1891 agreement, the Tribes were to “cede, convey, transfer, relinquish and

surrender, forever and absolutely . . . all [the Tribes’] right, title, and interest, of

every kind and character, in and to the lands, and the water rights appertaining

thereunto” for the sum of $600,000. H.R. Exec. Doc. No. 52-70, at 29, 30 (1892). 

Though Congress did not ratify this agreement, two years later the Secretary of

the Interior sent another commission to negotiate with the Tribes for the sale of

the land north of the Big Wind River. This time, the United States asked for

additional land and offered the Tribes $750,000. H.R. Exec. Doc. No. 53-51, at 4

(1894). Despite the higher offer, the Tribes refused three different proposals, and

no agreement was reached.10

Congressional activity resumed in 1904, when Representative Frank

Mondell of Wyoming introduced a bill to further reduce the Wind River

Reservation. The 1904 Mondell Bill was based on the 1891 and 1893 proposals. 

But by 1904, the Supreme Court had declared that Congress had plenary authority

10 Congress did successfully obtain the land around the Big Horn Hot

Springs through the Thermopolis purchase in 1897. 30 Stat. at 94. 

-24-
over relations with Native Americans, so Congress no longer needed tribal

approval to change reservation boundaries. See Lone Wolf v. Hitchcock, 187 U.S.

553, 565 (1903). As Representative Thomas Frank Marshall, the Chairman of the

Committee on Indian Affairs wrote, the 1904 Bill “propose[d] to reduce the

reservation, as suggested . . . at the time of the making of the agreement of

1891 . . . .” H.R. Rep. No. 58-2355, at 3 (1904). 

The Mondell Bill, however, differed from the 1891 agreement in several

respects. One amendment—and one the EPA and the Tribes point to—was the

elimination of the $600,000 sum certain payment. To that, Representative

Marshall explained, “[The Mondell Bill] follows as closely as possible, under the

changed conditions and the present policy of Congress relative to payments for

lands purchased from Indians, the agreement of 1891 and the bill prepared at the

time for carrying out the provisions of that agreement.” H.R. Rep. No. 58-2355,

at 4 (emphasis added). “[The bill] follows the now established rule of the House

of paying to the Indians the sums received from the ceded territory under the

provisions of the bill.” H.R. Rep. No. 58-2355, at 2; see also H.R. Rep. No. 58-

2355, at 8 (quoting letter from then-Acting Commissioner to the Secretary of the

Interior A. C. Tonner explaining structure of payment framework). Thus, to

comply with prevailing policy, the sum certain payment was excised and replaced

with a framework whereby lands would be sold at different times and at different

prices with the proceeds to be transferred to the Tribes. And, incidentally, it was

-25-
believed that the Tribes could realize greater compensation under such a

framework. H.R. Rep. No. 58-2355, at 4 (observing “[t]he amount which the

Indians would receive at $1 an acre would be $1,480,000”). As the Supreme

Court has previously recognized, Congress adopted “‘a new policy in acquiring

lands from the Indians [by] provid[ing] that the lands shall be disposed of to

settlers . . ., and to be paid for by the settlers, and the money to be paid to the

Indians only as it is received . . . from the settlers.’” Rosebud, 430 U.S. at 592

(footnote omitted) (alterations in original).

Given these congressional directives, in April 1904, Indian Inspector James

McLaughlin met with the Tribes and presented the terms of the Mondell Bill in a

series of meetings on the Wind River Reservation.11 McLaughlin opened by

stating, 

My friends, I am sent here at this time by the Secretary of

the Interior to present to you a proposition for the opening

of certain p[or]tions of your reservation for settlement by

the whites. It is believed that it will be to the best

interests of your two tribes to cede to the United States the

portions referred to.

11 McLaughlin, who had also negotiated the 1897 Thermopolis Purchase, 

negotiated many land agreements with Native American tribes, including the

Lower Brules, the Otoes, the Missourias, the Klamaths, the Modocs, the Yankton,

the Sioux, the Red Lake Chippewas, the Mille Lacs Chippewas, the Pah-Utes, and

the Standing Rock Sioux. James McLaughlin, My Friend the Indian 295 (1910). 

The Supreme Court has reviewed agreements he negotiated that resulted in

diminishment in a number of cases, including Rosebud and Hagen. 

-26-
Minutes of Council between James McLaughlin, U.S. Indian Inspector, and the

Indians of the Eastern Shoshone and Arapaho Tribes, at 2 (Apr. 19–21, 1904)

(emphasis added) (reproduced in JA 509–36) [Council Minutes]. But McLaughlin

explained that since his last agreement with the Tribes, Congress’s policy for

paying for ceded land had changed: “For several years past there has been a

sentiment in Congress . . . opposed to paying the Indians a lump sum

consideration for their lands. Instead of stipulating, or providing in the

agreement, a lump sum consideration for any tract of land, they have determined

upon giving the Indians the full benefit of the land by paying the Indians from the

proceeds of the sale of the land as whitemen settle upon it.” Council Minutes, at

3. McLaughlin explained to the Tribes that they would “receive more in the

aggregate than under the old lump sum agreements.” Council Minutes, at 4. 

McLaughlin advised the Tribes during negotiations that the boundaries of

the Reservation would change as a result of the Act, just as they would have

under the agreement in 1891 and the negotiations in 1893. He stated, 

I now wish to talk of the boundaries of the reservation and

the residue of land that will remain in your diminished

reservation. That being a very important matter. . . . The

tract to be ceded to the United States, as proposed by the

“Mondell Bill,” is estimated at 1,480,000 acres, leaving

800,500 acres in the diminished reservation. 

-27-
Council Minutes, at 6 (emphasis added).12 McLaughlin informed the Tribes that

“a large reservation is not in your interest,” while the reduction would be, and

that Congress could now unilaterally change the boundaries of the Reservation if

the Tribes did not agree. Council Minutes, at 7.

Conveying the purpose of the Mondell Bill, McLaughlin told the Tribes

that this agreement would allow the Tribes to “dispos[e] of the lands that you do

not need” and that they would “realiz[e] money from the sale of that land, which

will provide you with means to make yourselves comfortable upon your

reservation . . . .” Council Minutes, at 3. He also referred to the ceded lands as

“the public domain” and made clear the land on the north side of the Big Wind

River (part of the ceded territory), after the agreement, would be different: 

Those of you who have allotments on the north side of the

river, if you so desire, can have them cancelled and come

within the diminished reservation. * * * However, any of

you who retain your allotments on the other side of the

river can do so, and you will have the same rights as the

whiteman, and can hold your lands or dispose of them, as

you see fit. On the reservation, you will be protected by

12 We acknowledge the Supreme Court stated in Solem that a “few

scattered phrases” describing agreements as “reducing the reservation,” or “the

reservation as diminished,” do not indicate a clear congressional purpose to

diminish the boundaries of a reservation. 465 U.S. at 478; see also id. at 475 n.17

(reasoning “‘diminished’ was not yet a term of art in Indian law”). For as the

Court observed, “[I]t is unclear whether Congress was alluding to the reduction in

Indian-owned lands that would occur once some of the opened lands were sold to

settlers or to the reduction that a complete cession of tribal interests in the opened

area would precipitate.” Id. (citation omitted). But here we are not limited to a

few ambiguous phrases; rather, we are presented with a more complete set of

circumstances similar to those the Supreme Court credited in Rosebud. 

-28-
the laws that govern reservations in all your rights and

privileges.

Furthermore, all of you who may retain your allotments off

the reservation, will not lose any of your rights on the

reservation, and you have rights the same as if you

remained within the diminished reservation. You will

have rights to surplus lands, the timber etc, although your

home may be on the public domain. 

Council Minutes, at 14 (emphasis added). 

The tenor of the Tribes’ understanding of the agreement reflects that the

Reservation’s boundaries would be diminished. One representative for the

Eastern Shoshone told McLaughlin that his Tribe understood it was “parting with

[its lands] forever and [could] never recover [them] again.” Council Minutes, at

17. Long Bear, a chief of the Arapaho Tribe, proclaimed, “I understand what he

comes for . . . and I will tell what part of the Reservation I want to sell. . . . I

want to cede that portion of the reservation from the mouth of the Dry Muddy

Gulch in a direct line to the mouth of Dry or Beaver Creek below Stagner’s on

Wind River.” Council Minutes, at 9. Rev. Sherman Coolidge of the Arapaho

added he was glad McLaughlin had come “to purchase a portion of our

reservation. The proposed ceded portion has not been used except for

grazing. . . . We need the money that we will get from the sale of these lands for

improvements on the unceded portion.” Council Minutes, at 12. 

-29-
The Tribes and McLaughlin entered into an agreement, see Council

Minutes, at 27, and McLaughlin reported the progress back to Washington. 

Specifically, he wrote,

The diminished reservation leaves the Indians the most

desirable and valuable portion of the Wind River

Reservation and the garden spot of that section of the

country. It is bounded on the north by the Big Wind

River, on the east and southeast by the Big Popo-Agie

River, which, being never failing streams carrying a

considerable volume of water, give natural boundaries

with well-defined lines; and the diminished reservation,

approximately 808,500 acres . . . allows 490 acres for each

of the 1,650 Indians now belonging to the reservation. I

have given this question a great deal of thought and

considered every phase of it very carefully and became

convinced that the reservation boundary, as stipulated in

the agreement, was ample for the needs of the

Indians . . . . 

H.R. Rep. No. 58-3700, at 17 (1905) (emphasis added). But the 1904 Mondell

Bill as negotiated with the Tribes was never approved. Instead, it was amended

and codified as a new bill (the 1905 Act), which was approved by Congress on

March 3, 1905. The legislative history reveals almost no debate about the cession

and payment provisions of the 1905 Act; as discussed, most of the debate had

occurred in the drafting of the 1904 Act. According to the House Report on the

issue, the 1905 Act was “in harmony” with the Mondell Bill, with “the principal

changes . . . in form rather than substance.” H.R. Rep. No. 58-3700, at 6.

We believe the circumstances surrounding the 1905 Act most closely

resemble those in Rosebud. In 1901, McLaughlin was dispatched to negotiate

-30-
with the Indians on the Rosebud Reservation to cede unalloted portions of their

reservation. Rosebud, 430 U.S. at 590. They agreed to cede 416,000 acres for a

sum of $1,040,000, but the agreement was not ratified because it “‘provided that

the Government should pay for the lands outright.’” Id. at 591 (citation omitted). 

The Supreme Court observed it was “undisputed” that had the agreement been

ratified, it would have changed the reservation’s boundaries. Id. Working from

that baseline, the Court concluded, “An examination of the legislative processes

which resulted in the 1904 Act convinces us . . . that this purpose was carried

forth and enacted.” Id. at 592. 

Similarly, here, the unratified 1891 agreement with the Tribes served as a

predicate for the 1905 Act. Indeed, in introducing the Mondell Bill,

Representative Mondell had the 1891 agreement read into the record and then

offered amendments to that agreement to reflect the revisions discussed. 38

Cong. Rec. 5,245, 5,245, 5,246–47 (1904). Thus, the actual congressional record

belies the EPA’s finding that no continuity of purpose existed between the 1891

agreement and the 1905 Act. That provisions were revised to reflect the

McLaughlin negotiations and the prevailing policy on compensating Native

Americans for ceded land at the time is insufficient reason for severing and

rendering irrelevant the circumstances prior to 1904. 

Additionally, this case is unlike Solem because Congress, through its

legislative history, explicitly stated its intent to cede portions of the Reservation. 

-31-
See Solem, 465 U.S. at 477 (Congress enacted a “sell and dispose” act). 

Moreover, the 1905 Act bears the same hallmarks that, as the Supreme Court put

it, made Solem a “more difficult” case and evidenced diminishment. Compare id.

at 474 (explaining act permitted “Indians already holding allotments on the

opened lands to obtain new allotments . . . ‘within the respective reservations thus

diminished’” (citation omitted)), with 33 Stat. at 1016 (“[A]nd any Indian who

has made or received an allotment of land within the ceded territory shall have the

right to surrender such allotment and select other lands within the diminished

reserve in lieu thereof . . . .”).13 In the end, Congress’s consistent attempts at the

13 Likewise, Congress’s inclusion or removal of certain provisions in the

1905 Act may cut against diminishment. First, the Act included a provision that

retained the lease rights of one Asmus Boysen and gave him the option to

purchase preferential land. 33 Stat. at 1020. Boysen’s agreement with the Tribes

contained a clause that would have terminated the lease upon extinguishment of

the Tribes’ title to covered lands. JA 4604. The EPA’s decision opined that

Congress’s concern with the Boysen lease—particularly, its potential for clouding

the title of certain opened lands—evinced an intent not to diminish the

Reservation’s boundaries. JA 4606–07. The EPA’s understanding of Congress’s

treatment of the Boysen lease was limited to a finding that “the 1905 Act would

retain a Tribal trust interest in the opened lands and that those lands would not be

returned to the public domain.” JA 4606. But as we explained in step one of our

analysis, the existence of a trust relationship is not determinative of

diminishment, and, unlike Hagen, this is not a “public domain” case. 

Additionally, the EPA pointed to Congress’s removal of a provision that would

have required the United States to pay the Tribes for sections 16 and 36 (as

school lands) or equivalent lands of each township. JA 4608–09. The Supreme

Court found the inclusion of such a provision probative of diminishment in

Rosebud and Yankton Sioux. See Rosebud, 430 U.S. at 599–601; Yankton Sioux,

522 U.S. at 349–50. But the record in this case reveals that Wyoming may have

received federal land elsewhere in exchange, obviating the need for a school lands

provision.

-32-
turn of the century to purchase the disputed land compel the conclusion that this

intent continued through the passage of the 1905 Act. And the statements in the

legislative history about the diminishment of the reservation, when taken together

with the Act’s plain language, provide ample support for the conclusion Congress

understood it was separating the land north of the Big Wind River from the rest of

the Wind River Reservation and indeed intended to do so. 

C. Subsequent Treatment of the Area

Third and finally, and “[t]o a lesser extent,” we can consider “Congress’s

own treatment of the affected areas, particularly in the years immediately

following the opening,” as well as “the manner in which the Bureau of Indian

Affairs and local judicial authorities dealt with unallotted open lands.” Solem,

465 U.S. at 471. “[A]s one additional clue as to what Congress expected would

happen,” we also “look to the subsequent demographic history of opened lands.” 

Id. at 471–72. But although such evidence can buttress a finding of diminishment

based on the statutory text, the Supreme Court “has never relied solely on this

third consideration.” Parker, 136 S. Ct. at 1081. Accordingly, subsequent events

“‘cannot undermine substantial and compelling evidence from an Act and events

surrounding its passage.’” Osage Nation, 597 F.3d at 1122 (quoting Yazzie, 909

F.2d at 1396). Our review of the subsequent treatment of the area is therefore

brief and ultimately does not impact our conclusion Congress intended to

diminish the Reservation by the 1905 Act.

-33-
From the outset, we note the parties have provided volumes of material

evidencing the treatment of the ceded land after the 1905 Act. Unsurprisingly,

each side has managed to uncover treatment by a host of actors supporting its

respective position. Recognizing this inevitability, the Supreme Court has warned

that at times “subsequent treatment” may be “so rife with contradictions and

inconsistencies as to be of no help to either side.” Solem, 465 U.S. at 478. 

Because we are unable to discern clear congressional intent from the subsequent

treatment, we find it is of little evidentiary value. See also JA 4624 (the EPA

conceding “Congressional and Executive Branch references to the opened area

were inconsistent”); JA 3636 (Solicitor indicating “[t]he evidence from the years

immediately after the 1905 Act indicates some inconsistent treatment of the 1905

area”).14

Nonetheless, we examine some of the more germane evidence. Perhaps the

most telling indication that Congress intended to diminish the Reservation’s

boundaries in the 1905 Act is the Indian Reorganization Act, 48 Stat. 984 (1934),

in which Congress began implementing its new policy of Indian selfdetermination. But because the Tribes opted out of the Reorganization Act that

would have restored the ceded lands, in 1939, Congress authorized the restoration

14 We agree with Judge Lucero that the Solem third step tells us little of

value, and in fact “irrationally” requires us to infer intent from subsequent

demographic developments. The better guide is statutory text and the historical

context that drove Congressional action.

-34-
of “all undisposed-of surplus or ceded lands . . . which [we]re not at present under

lease or permit to non-Indians,” and restored to tribal ownership the “balance of

said lands progressively as and when the non-Indians owned the lands.” 53 Stat.

1128, 1129–30 (1939). In administering the land restoration, the Secretary of the

Interior sought to “add” the restored lands to, or “make them part of,” the

Reservation. For example, in one order, the Secretary stated,

Now, Therefore, by the virtue of authority vested in the

Secretary of the Interior by section 5 of the Act of July 27,

1939 (53 Stat. 1128-1130), I hereby find that the

restoration to tribal ownership of the lands described

above, which are classified as undisposed of, ceded lands

of the Wind River Reservation, Wyoming, . . . will be in

the tribal interest, and they are hereby restored to tribal

ownership for the use and benefit of the ShoshoneArapahoe Tribes of Indians of the Wind River Reservation,

Wyoming, and are added to and made part of the existing

Wind River Reservation . . . . 

9 Fed. Reg. 9,754 (1944) (emphasis added). It is difficult to conceive why the

Secretary would have used such language if indeed the ceded lands at all relevant

times remained part of the Reservation. 

Subsequent statements made by Congress also support the conclusion

Congress believed the 1905 Act changed the Reservation’s boundaries. In 1907,

Congress extended the time for entry onto the ceded territory. In that Act,

Congress referred to the land as “lands formerly embraced in the Wind River of

Shoshone Indian Reservation, in Wyoming, which were opened for entry.” 34

Stat. 849 (1907) (emphasis added); see also H.R. Doc. No. 64-1757, at 9 (1916)

-35-
(stating “the [irrigation] project under consideration is within the ‘ceded lands’

portion of what was formerly included in the Wind River or Shoshone Indian

Reservation” (emphasis added)). Again, Congress’s consistent reference to lands

that were formerly part of the Reservation is probative of diminishment. 

Likewise, some maps from the period indicate the Reservation only

included the unopened lands. See JA 3638 (explaining 1907 map by the State of

Wyoming and 1912 map by the General Land Office purported to show the

Reservation’s boundaries only encompassed lands unopened by the 1905 Act). 

But, as the solicitor pointed out in her 2011 opinion, other maps merely reference

the ceded lands as “open lands.” Id. Ultimately, we agree with the solicitor that

“[t]hese references are ambiguous and inconsistent at best.” Id. 

We also briefly consider the subsequent demographics of the ceded area,

though this consideration is the least probative of congressional intent. Solem,

465 U.S. at 471–72. As we have previously stated, “‘subsequent events and

demographic history can support and confirm other evidence but cannot stand on

their own; by the same token they cannot undermine substantial and compelling

evidence from an Act and events surrounding its passage.’” Osage Nation, 597

F.3d at 1122 (quoting Yazzie, 909 F.2d at 1396). Here, the demographic history is

mixed. On the one hand, only a small portion of the ceded land was ultimately

sold to non-Indians because of disinterest in the area. See JA 3638. On the other

hand, as the Wyoming Supreme Court has noted, roughly ninety-two percent of

-36-
the population of Riverton—the largest township on the ceded land—is nonIndian. Yellowbear, 174 P.3d at 1283. These mixed demographics do not

establish that “non-Indian settlers flooded into the opened portion,” causing the

area to “los[e] its Indian character,” Solem, 465 U.S. at 471–72; by the same

token, they do not undermine our conclusion that the statutory language and

historical context of the 1905 Act compel a finding of diminishment. 

Finally, jurisdictional and judicial treatment of the area is also mixed and

thus has little probative value. Wyoming has previously exercised criminal

jurisdiction over parts of the disputed area. For example, in a 1960 opinion the

Wyoming Supreme Court found the state had jurisdiction over a crime that

occurred north of Riverton in the ceded lands. Blackburn v. State 357 P.2d 174,

179–80 (Wyo. 1960). Ten years later, the court held the state had jurisdiction

over a murder committed in Riverton. State v. Moss, 471 P.2d 333, 339 (Wyo.

1970). And in Yellowbear, the court applied the Solem factors and concluded

“that it was the intent of Congress in passing the 1905 Act to diminish the Wind

River Indian Reservation.” 174 P.3d at 1284. The court thus determined the state

had jurisdiction to prosecute Yellowbear. Id. Upon habeas review, we declined

to disturb that decision. Yellowbear, 380 F. App’x at 743. 

On the other hand, both Wyoming and several federal agencies have

exercised civil jurisdiction over the disputed area. Aple. EPA Br. 65–66. And in

deciding Dry Creek Lodge, Inc. v. Arapahoe & Shoshone Tribes, we summarily

-37-
referred to the town of Riverton as being within the boundaries of the

Reservation. 623 F.2d 682, 683 (10th Cir. 1980) (“Plaintiffs’ land is within the

exterior boundaries of the Wind River Reservation of the Shoshone and Arapahoe

Indians in Wyoming.”). But as the EPA acknowledged in its decision below, Dry

Creek is “generally unrevealing regarding the legal effect of the 1905 Act,” given

that we did not consider the 1905 Act in light of the Solem criteria. JA 4645.

 Adding to the varied treatment is the Wyoming Supreme Court’s decision

in In re General Adjudication of All Rights to Use Water in the Big Horn River

System (Big Horn I), 753 P.2d 76 (Wyo. 1988), aff’d sub nom. Wyoming v. United

States, 492 U.S. 406 (1989), overruled in part by Vaughn v. State, 962 P.2d 149

(Wyo. 1998). But Big Horn I actually tells us little about how courts have treated

the Wind River Reservation. Contrary to the Tribes’ assertion, the court in Big

Horn I did not interpret the 1905 Act as maintaining a larger Reservation. 

Instead, the court merely held the 1905 Act did not evince a clear intent to

abrogate the water rights granted to the entire Wind River Reservation at its

creation in 1868. Big Horn I, 753 P.2d at 93–94. The court never stated that its

allocation of water rights was based upon the Reservation boundaries, nor did it

make a specific finding about those boundaries.

Nevertheless, the Northern Arapaho argue Big Horn I bars Wyoming from

challenging the EPA’s boundary determination on res judicata grounds. But, as

detailed above, Big Horn I concerned the allocation of water rights, specifically

-38-
the priority dates for those rights. 753 P.2d at 83. The special master’s

conclusion that the 1905 Act did not sever the 1868 priority date for water rights,

see id. at 92, is not determinative on the issue of diminishment—the issues are

mutually exclusive, and Wyoming is not relitigating the water rights

determination. Indeed, in dispensing of the issue, the Wyoming Supreme Court

merely stated, “A reservation of water with an 1868 priority date is not

inconsistent with the permit provisions of the pre-Winters 1905 Act.” Id. at 93. 

Even more detrimental to the Northern Arapaho’s position, the Wyoming

Supreme Court has since expressly rejected the Tribe’s characterization of Big

Horn I. In Yellowbear, the court stated “while [the majority and the dissent]

disagreed over whether reserved water rights continued to exist in the ceded

lands, the majority and dissent in Big Horn River agreed that the reservation had

been diminished.” 174 P.3d at 1283 (emphasis added). 

In sum, on balance the subsequent treatment of the ceded lands neither

bolsters nor undermines our conclusion that the 1905 Act diminished the Wind

River Reservation.

III. Conclusion

For the foregoing reasons, we find Congress diminished the boundaries of

the Wind River Reservation. We therefore GRANT Wyoming’s petition for

review, VACATE the EPA’s order, and REMAND for further proceedings

consistent with this opinion.

-39-
14-9512 & 14-9514, Wyoming v. United States Environmental Protection Agency 

LUCERO, J., dissenting. 

 The “Indian right of occupancy of tribal lands, whether declared in a treaty or 

otherwise created, has been stated to be sacred.” Lone Wolf v. Hitchcock, 187 U.S. 553, 

564 (1903). Our respect for this right stems, or should stem, from Tribes’ status as 

“separate sovereigns pre-existing the Constitution.” Santa Clara Pueblo v. Martinez, 436 

U.S. 49, 56 (1978). Although Congress possesses the unilateral authority to diminish the 

reservations of these sovereign nations, Solem v. Bartlett, 465 U.S. 463, 470 n.11 (1984) 

(citing Lone Wolf, 187 U.S. 553), we must not lightly assume that Congress has 

exercised this destabilizing power. Only when express statutory language, legislative 

history, and surrounding circumstances “point unmistakably to the conclusion that” a 

reservation was diminished should we read a statute as having that effect. DeCoteau v. 

Dist. Cty. Ct. for Tenth Jud. Dist., 420 U.S. 425, 445 (1975). 

 In 1905, Congress passed an act transferring certain lands in the Wind River 

Reservation to the United States. The federal government was to act as trustee by selling 

the lands and paying the Indians the proceeds. Act of March 3, 1905, 33 Stat. 1016 (the 

“1905 Act” or the “Act”). From this placement of property into trust status in exchange 

for a conditional promise of payment, my colleagues in the majority infer clear 

congressional intent to diminish the Wind River Reservation. I cannot agree. By 

deriving an intent to diminish absent sum-certain payment or statutory language restoring 

lands to the public domain, the majority opinion creates a new low-water mark in 

diminishment jurisprudence. Applying the three-step analysis from Solem, 465 U.S. at 
2 

470-71, I would hold that the 1905 Act did not diminish Reservation boundaries. 

Accordingly, I respectfully dissent. 

I

 Our diminishment analysis begins with the statutory text. The Court has stated 

that “language evidencing the present and total surrender of all tribal interests,” when 

coupled with an “unconditional commitment from Congress to compensate the Indian 

tribe for its opened land,” creates a presumption of diminishment. Solem, 465 U.S. at 

470-71; see also DeCoteau, 420 U.S. at 445-49 (finding diminishment based on language 

of cession and sum-certain payment). The 1905 Act states that the Indians “cede, grant, 

and relinquish to the United States, all right, title, and interest” to certain lands “within 

the said reservation.” 33 Stat. at 1016. But the United States did not agree to pay a sum 

certain. Instead, the Act provides that “the United States shall act as trustee for said 

Indians to dispose of said lands and to expend for said Indians and pay over to them the 

proceeds received from the sale thereof only as received, as herein provided.” Id. at 1021 

(emphasis added). Moreover, the Act states that “nothing in this agreement contained 

shall in any manner bind the United States to purchase any portion of the lands herein 

described or to dispose of said lands except as provided herein, or to guarantee to find 

purchasers for said lands.” Id. at 1020. Citing the Act’s designation of a portion of the 

sale proceeds for per capita payments, the majority adopts the euphemism “hybrid 

payment scheme.” (Majority Op. 20.) However, the terms of the statute unambiguously 

reflect a conditional promise to pay. 
3 

Because the 1905 Act lacked sum-certain payment, the majority opinion’s reliance 

on sum-certain cases is misplaced. It repeatedly asserts that the language of the 1905 

Act, like the statutory language in DeCoteau, is “precisely suited” to diminishment. (See, 

e.g., Majority Op. 14 (citing DeCoteau, 420 U.S. at 445).) But when the Court in 

DeCoteau made that observation, it was comparing the statutory language of an 1889 

agreement to “that used in the other sum-certain, cession agreements” ratified in the same 

act. 420 U.S. at 446 (emphasis added). The DeCoteau Court distinguished both Seymour 

v. Superintendent, 368 U.S. 351 (1962), and Mattz v. Arnett, 412 U.S. 481 (1973), in 

part, on the ground that the acts at issue in those cases conditioned payment to the tribes 

on the “uncertain future proceeds of settler purchases”—precisely the situation presented 

here. DeCoteau, 420 U.S. at 448. In contrast, the 1891 act in DeCoteau “appropriate[d] 

and vest[ed] in the tribe a sum certain.” Id. 

The 1905 Act differs from legislation deemed to have diminished reservations in 

another important respect: It did not restore the lands at issue to the public domain. Cf. 

id. at 446 (citing legislators’ statements that “ratified agreements would return the ceded 

lands to the ‘public domain’” to support claim that agreements unquestionably 

diminished reservations). Because the lands at issue here were held in trust under the 

Act, they remained Indian lands. In Ash Sheep Co. v. United States, 252 U.S. 159 

(1920), the Tribe “ceded, granted, and relinquished to the United States all of their right, 

title and interest.” Id. at 164 (quotations omitted). However, the government did not 

provide unconditional payment, promising only to give the Indians the future proceeds of 

any land sales. Id. at 164-65. And, in language nearly identical to the 1905 Act, the 
4 

statute stated that the United States was not bound to purchase or sell the affected lands 

but rather to “act as trustee” in their disposal. Id. at 165-66. The Court determined, 

based on this language, that although the Indians had “released their possessory right to 

the government,” the lands remained “Indian lands” because any benefits derived 

therefrom would belong to the Indians as beneficiaries and not the government as trustee 

until the lands were sold. Id. at 166.1

 

 Admittedly, the retention of a beneficial interest is not dispositive of reservation 

status. See Rosebud Sioux Tribe v. Kneip, 430 U.S. 584, 601 n.24 (1977). But the 

majority too easily dismisses the trust status of the lands at issue. (See Majority Op. at 

21-22.) “The notion that reservation status of Indian lands might not be coextensive with 

tribal ownership was unfamiliar at the turn of the century.” Solem, 465 U.S. at 468. 

Accordingly, although it is not determinative, Congress’ decision not to restore these 

lands to the public domain cuts strongly against the majority’s conclusion that the 

Reservation was diminished. 

 Given the absence of sum-certain payment or restoration of lands to the public 

domain, we could easily interpret the language of cession contained in the 1905 Act as 

merely opening portions of the Wind River Reservation to settlement.2

 In assessing 

 1

 The majority states that Ash Sheep is seldom cited in more recent diminishment 

cases because it addresses the different issue of whether lands became “public lands.” 

(Majority Op. 21-22.) But in DeCoteau, a case upon which the majority relies, the Court 

cites Ash Sheep in distinguishing Mattz based on the absence of sum-certain payment. 

See DeCoteau, 420 U.S. at 448. 

2

 As in Solem, the 1905 Act provides that Indians who held an allotment within 

the opened territory would be permitted to obtain a new allotment in the unopened area, 
5 

statutory language nearly identical to the 1905 Act, the Eighth Circuit concluded that the 

Devils Lake Indian Reservation had not been diminished. United States v. Grey Bear, 

828 F.2d 1286 (8th Cir.), vacated in part on other grounds on reh’g en banc, 836 F.2d 

1088 (8th Cir. 1987). Specifically, the court held that although the language “do hereby 

cede, surrender, grant, and convey to the United States all their claim, right, title, and 

interest” was suggestive of diminishment, id. at 1290 (emphasis omitted) (quoting Act of 

April 27, 1904, ch. 1620, 33 Stat. 321-22), it did not “evince a clear congressional intent 

to disestablish the Devils Lake Reservation” absent an “unconditional commitment” by 

Congress to pay for the ceded lands, id. 

The majority attempts to distinguish Grey Bear, noting that the legislative history 

of the act at issue there was not extensive and that subsequent treatment of the area 

weighed against a finding of diminishment. (Majority Op. 17 n.6.) But the majority does 

not appear to rest its holding in this case on the second and third steps of the Solem 

analysis. Instead, it claims that the “express language of cession in the 1905 Act 

indicates Congress intended to diminish the boundaries of the Wind River Reservation.” 

(Id. at 22.) The majority thus reaches a conclusion squarely opposite to one of our sibling 

circuits, creating a needless circuit split. 

 

referring to the latter as the “diminished reserve.” 33 Stat. at 1016; Solem, 465 U.S. at 

474 (describing unopened areas as “reservations thus diminished”). But the Supreme 

Court explained that this phrase “cannot carry the burden of establishing an express 

congressional purpose to diminish” because at the time of the Act, “‘diminished’ was not 

yet a term of art in Indian law.” Solem, 465 U.S. at 475 & n.17. Thus, Congress “may 

well have been referring to diminishment in common lands and not diminishment of 

reservation boundaries.” Id. Similarly, references to a reservation “in the past tense” 

should not “be read as a clear indication of congressional purpose to terminate.” Mattz, 

412 U.S. at 498-99. 
6 

 The Supreme Court has counseled that “[w]hen we are faced with . . . two 

possible constructions, our choice between them must be dictated by a principle deeply 

rooted in this Court’s Indian jurisprudence: Statutes are to be construed liberally in favor 

of the Indians, with ambiguous provisions interpreted to their benefit.” Cty. of Yakima v. 

Confederated Tribes & Bands of Yakima Indian Nation, 502 U.S. 251, 269 (1992) 

(quotation and alteration omitted). Adhering to that principle in this case, we must read 

the 1905 Act as providing for sale and opening of lands rather than diminishment. 

II

In very limited circumstances, courts have been willing to find diminishment even 

absent “explicit language of cession and unconditional compensation.” Solem, 465 U.S. 

at 471. But that is true only if surrounding circumstances “unequivocally reveal a 

widely-held, contemporaneous understanding that the affected reservation would shrink 

as a result of the proposed legislation.” Id. A “few phrases scattered through the 

legislative history” are insufficient to manufacture clear congressional intent to diminish 

if a plain statement of that objective is lacking in the statutory text. Id. at 478. 

 Legislative history surrounding two ancillary portions of the 1905 Act counsel 

against an intent to diminish. First, Congress chose to omit a school lands provision from 

the 1905 Act, demonstrating its view that the opened lands retained their Reservation 

status. A precursor bill, presented to Congress in 1904, initially provided that the United 

States would pay $1.25 per acre for sections 16 and 36, or equivalent lands, in the opened 

townships. 38 Cong. Rec. H5247 (1904). This provision mirrored the Wyoming 

Enabling Act, which grants sections 16 and 36 of each township to the state for school 
7 

purposes unless those lands are sold or disposed of, in which case the state may take 

other lands in lieu. Wyoming Enabling Act, ch. 664, § 4, 26 Stat. 222, 222-23 (1890). 

During debate on the 1904 bill, Representative Mondell proposed to strike the school 

lands provision. 38 Cong. Rec. H5247. He explained that although “the bill originally 

provided that the State should take lands on the reservation” for the price of $1.25 per 

acre, eliminating the school lands provision would “leav[e] the State authorized under the 

enabling act to take lieu lands.” Id. (statement of Rep. Mondell) (emphasis added). Both 

Mondell’s statement and the decision to omit the provision evince the belief that sections 

16 and 36 would remain part of the Reservation. The House Committee on Indian 

Affairs later reported that it had adhered to this policy in drafting the bill that would 

ultimately become the 1905 Act. See H.R. Rep. No. 58-3700, pt. 1, at 7 (1905) (stating 

that it had been “deemed wise by the committee to adhere to the policy laid down in the 

former bill and agreement,” under which there was no school lands provision and 

“Indians [were] to receive the same rates from settlers for sections 16 and 36 as paid for 

other lands”).3

 

Conversely, if a school lands provision is included in a statute, the Supreme Court 

has been more apt to find congressional intent to diminish. In Rosebud, for example, the 

 3

 Although the Wyoming Enabling Act did not exempt reservations from the grant 

of sections 16 and 36 to the state for school purposes, the Wyoming Constitution 

disclaims “all right and title to . . . all lands lying within said limits owned or held by any 

Indian or Indian tribes.” Wyo. Const. art. XXI, § 26. Because “Congress is presumed to 

act with knowledge of controlling constitutional limitations” when it enacts new statutes, 

Golan v. Gonzales, 501 F.3d 1179, 1183 (10th Cir. 2007), the decision to omit the school 

lands provision is further evidence Congress believed the opened lands to retain their 

reservation status. 
8 

Court held that the inclusion of a similar school lands provision evinced “congressional 

intent to disestablish Gregory County from the Rosebud Reservation, thereby making the 

sections available for disposition to the State of South Dakota for school sections.” 430 

U.S. at 601 (quotation omitted); see also South Dakota v. Yankton Sioux Tribe, 522 U.S. 

329, 349-50 (1998) (inclusion of school lands provision indicative of intent to diminish).4 

The majority notes that the State of Wyoming may have received federal land elsewhere 

as a result of Congress’ decision to omit the school lands provision. (Majority Op. 32 

n.13.) But that is exactly the point. By striking the provision, Congress recognized that 

Wyoming could take lieu lands elsewhere, rather than pay $1.25 for “lands on the 

reservation.” 38 Cong. Rec. H5247 (statement of Rep. Mondell) (emphasis added); see 

also 26 Stat. at 222-23. 

Also weighing against a finding of diminishment is a provision granting Asmus 

Boysen a preferential right to lease new lands “in said reservation” in lieu of his existing 

lease rights. 33 Stat. at 1020. The provision was opposed by a minority in the House of 

Representatives, who argued that Boysen should not be granted preferential rights 

because his lease would terminate upon passage of the Act, and because “other persons 

desiring to enter and settle upon the lands to be opened” should stand on equal footing. 

 4

 In contrast to the Wyoming Enabling Act, the statute admitting North and South 

Dakota into the Union expressly provided that sections 16 and 36 “embraced in 

permanent reservations” would not “be subject to the grants . . . of [the] act.” Act of 

February 22, 1889, 25 Stat. 676, 679. However, as discussed in n.3, supra, the Wyoming 

Constitution served a similar function by disclaiming “all right and title” to lands held by 

Indian Tribes. Wyo. Const. art XXI, § 26. Accordingly, even if the grant of sections 16 

and 36 on the Wind River Reservation was not expressly prohibited by the Wyoming 

Enabling Act, it makes sense that Congress would not have provided for Wyoming to 

take lands to which the state had “forever disclaim[ed] all right and title.” Id. 
9 

H.R. Rep. No. 58-3700, pt. 2, at 2, 3 (emphasis added). By describing the “lands to be 

opened” as being “in said reservation,” 33 Stat. at 1020, the 1905 Act demonstrates 

Congress’ understanding that the opened areas would retain their reservation status.5

 

 The majority relies on a prior history of negotiations to conclude that the 1905 Act 

resulted in diminishment, citing Rosebud for the proposition that implied continuity in 

purpose from a prior agreement is informative. (See Majority Op. 31 (citing Rosebud, 

430 U.S. at 590-92); see also id. at 15 n.2.) But the negotiation history presented here 

differs markedly from that considered by the Court in Rosebud. In Rosebud, the Rosebud 

Sioux Tribe reached an agreement with the United States to diminish reservation 

boundaries in 1901. 430 U.S. at 587. Although Congress failed to ratify the agreement, 

the Court concluded that the agreement’s purpose was carried out in subsequent acts 

passed in 1904, 1907, and 1910. Id. at 587-88, 592. 

There were several factors in Rosebud that are not present in this case. Notably, a 

mere three years passed between the 1901 agreement and the 1904 act in Rosebud. It 

should be unsurprising that congressional intent remained static for such a brief period. 

 5

 Although the trust status of lands is not dispositive of the diminishment issue, the 

inclusion of the Boysen provision is further evidence that the opened lands were placed in 

trust for the benefit of the Tribes. Boysen had previously entered into a mineral lease 

with the Tribes that included portions of the opened area. The terms of the lease 

provided it would terminate “in the event of extinguishment . . . of the Indian title to the 

lands covered by” the agreement. As discussed, supra, a minority opposed to the 

provision argued that there was no need to grant Boysen preferential rights to the opened 

lands because his existing lease rights would automatically terminate upon passage of the 

1905 Act. But as Representative Marshall, the chairman of the subcommittee that 

considered the Boysen provision, explained, Indian title would not be extinguished 

because “these lands are not restored to the public domain, but are simply transferred to 

the Government of the United States as trustee for these Indians.” 39 Cong. Rec. H1945 

(1905) (statement of Rep. Marshall). 
10 

Here, my colleagues rely extensively on a proposed agreement from 1891, nearly a 

generation prior to passage of the 1905 Act. (See Majority Op. 24, 31.) 

Further, in Rosebud the reason Congress failed to ratify the prior agreement “was 

not jurisdiction, title, or boundaries” but “simply put, money.” 430 U.S. at 591 n.10 

(quotation omitted). The 1904 act was essentially identical to the 1901 agreement other 

than the form of payment. Id. at 594-97. In contrast, the government and Tribes in this 

case were unable to reach an agreement as to the particular lands to be opened in either 

1891 or 1893. In 1891, certain members of Congress called for the opening of more 

lands than what was provided for in the proposed agreement. H.R. Doc. No. 52-70, at 7-

8 (1892). And the Tribes rejected three separate counteroffers in 1893, indicating they 

did not wish to sell the lands under discussion. H.R. Doc. No. 53-51 (1894). Thus, 

unlike the three-year delay in Rosebud from an agreement that went unratified because of 

concerns over the manner of payment, we are presented with a fourteen-year halt 

following negotiations that failed because the parties could not agree on material terms. 

Not only did a significant period of time elapse between the 1891 negotiations and 

the 1905 Act in this case, but any continuity of purpose was also disrupted by intervening 

agreements regarding cession of other portions of the Reservation. In 1896, for example, 

Inspector McLaughlin successfully negotiated the Thermopolis Purchase Act, under 

which the Tribes ceded the Big Horn Hot Springs to the United States in exchange for a 

sum-certain payment of $60,000. Act of June 7, 1897, 30 Stat. 62, 93-94. At a council 

meeting in 1922, McLaughlin expressly distinguished the agreements underlying the 

1897 and 1905 Acts, stating that they were “entirely distinct and separate” and that under 
11 

the 1905 Act, “the government simply acted as trustee for disposal of the land north of 

the Big Wind River.” 

The absence of a continuity of purpose to diminish the Reservation is further 

evidenced by the negotiations preceding passage of the 1905 Act. In his 1903 

negotiations with the Rosebud Tribe, McLaughlin stated that he was there “to enter into 

an agreement which is similar to that of two years ago, except as to the manner of 

payment.” Rosebud, 430 U.S. at 593. In this case, McLaughlin did not tell the Tribes in 

1904 that he sought to reopen the 1891 or 1893 negotiations. And although the majority 

quotes McLaughlin’s use of the word “cede,” (Majority Op. 26), he used that term 

interchangeably with the concept of “opening . . . certain portions of [the] reservation for 

settlement by the whites.” Similarly, any references to a diminished reservation “may 

well have been referring to diminishment in common lands and not diminishment of 

reservation boundaries.” Solem, 465 U.S. at 475 & n.17. 

Looking to the totality of the circumstances surrounding the 1905 Act, it cannot be 

said that they “unequivocally reveal a widely-held, contemporaneous understanding that 

the affected reservation would shrink as a result of the proposed legislation.” Solem, 465 

U.S. at 471 (emphasis added). At best, the historical record is mixed regarding Congress’ 

intent. As such, it is insufficient to overcome ambiguity in the statutory text. 

III

 At the third step of the Solem analysis, we consider “[t]o a lesser extent . . . events 

that occurred after the passage of a surplus land act to decipher Congress’s intentions.” 
12 

Solem, 465 U.S. at 471. But this third prong comes into play only at the margins.6

 If “an 

act and its legislative history fail to provide substantial and compelling evidence of a 

congressional intention to diminish Indian lands, we are bound by our traditional 

solicitude for the Indian tribes to rule that diminishment did not take place and that the 

old reservation boundaries survived the opening.” Solem, 465 U.S. at 472. 

Because the statutory text and legislative history in this case fail to provide 

compelling evidence of congressional intent to diminish, we need not consider this third 

prong. Even if we did, however, I agree with the majority that the post-Act record is so 

muddled it does not provide evidence of clear congressional intent. (Majority Op. 34.)7 

But, as with the first two steps in the analysis, this lack of clarity must not be treated as a 

 6

 Although I acknowledge that controlling precedent permits courts to consider 

post-enactment events, I feel compelled to remark on the irrational nature of such an 

inquiry. The demographic makeup of an area decades or more following passage of a 

statute cannot possibly tell us anything about the thinking of a prior Congress. See Philip 

P. Frickey, A Common Law for Our Age of Colonialism: The Judicial Divestiture of 

Indian Tribal Authority Over Nonmembers, 109 Yale L.J. 1, 19 (1999) (noting “[t]he 

conceptual problem with this approach, of course, is that postenactment developments 

reveal nothing about original congressional intent, much less intent sufficiently clear to 

satisfy the canon” requiring ambiguous statutes to be construed in favor of tribal 

interests). The Court itself has apparently recognized the dubiousness of this analysis, 

referring to “de facto” diminishment as a “necessary expedient.” Solem, 465 U.S. at 471, 

472 n.13. 

The third step of the Solem analysis cannot be meaningfully described as a tool to 

decipher congressional intent. Rather, it is a means of ignoring that intent. Courts should 

be loath to abandon the proper tools of statutory interpretation in any context, but to do so 

with respect to Indian law is particularly perverse given our canon of construction that 

“statutes are to be construed liberally in favor of the Indians.” Confederated Tribes & 

Bands of Yakima Indian Nation, 502 U.S. at 269 (quotation and alteration omitted). 

7

 I also agree with the majority that this controversy has not been rendered moot 

and that the Wyoming Farm Bureau has standing. (See Majority Op. 10-11 n.1.) 

 
13 

neutral element. Because we apply a “presumption that Congress did not intend to 

diminish,” Solem, 465 U.S. at 481, proponents of diminishment must show that “nonIndian settlers flooded into the opened portion of a reservation and the area has long since 

lost its Indian character,” id. at 471. The appellants have not met this burden. 

Land sales in the opened area were largely a failure. By 1915, less than 10% of 

the land had been sold to non-Indians, prompting the Department of the Interior (“DOI”) 

to indefinitely postpone further sales. Less than 15% of the opened area was ultimately 

transferred to non-Indians. Cf. Yankton Sioux Tribe, 522 U.S. at 339 (noting that 

approximately 90% of unallotted tracts were settled in that case); Rosebud, 430 U.S. at 

605 (same). The DOI continued to allot parcels in the opened lands to Tribal members, 

and in 1939, Congress restored tribal ownership over the unsold land. Act of July 27, 

1939, ch. 387, 53 Stat. 1128. Today, approximately 75% of the lands opened for 

settlement by the 1905 Act is held in trust by the United States for the benefit of the 

Tribes and their members. 

Despite the sometimes conflicting treatment of the area by non-Indian authorities, 

(see Majority Op. 34-39), there can be little doubt that most of the opened area retains its 

Indian character. Accordingly, we face no risk of upsetting “justifiable expectations,” 

Rosebud, 430 U.S. at 605, by construing the 1905 Act as maintaining Reservation 

boundaries. 

IV

 We consider in this case an Act that began with Inspector McLaughlin’s warning 

to the Tribes that “Congress had the right to legislate for the opening of Indian 
14 

reservations without consulting the Indians or obtaining their consent.” Recognizing that 

Congress possesses the nearly unfettered power to impose its will, leaving the Tribes “no 

choice but to consent,” the Court has held that “any doubtful expressions in [legislation] 

should be resolved in the Indians’ favor.” Choctaw Nation v. Oklahoma, 397 U.S. 620, 

631 (1970). This rule must be given “the broadest possible scope” in the diminishment 

context. DeCoteau, 420 U.S. at 447. In interpreting the 1905 Act, we must bear in mind 

the government’s “moral obligations of the highest responsibility and trust, obligations to 

the fulfillment of which the national honor has been committed.” United States v. 

Jicarilla Apache Nation, 564 U.S. 162, 176 (2011) (citation and quotations omitted). 

With this heavy thumb on the scale, I would hold that the 1905 Act did not diminish the 

Wind River Reservation. I respectfully dissent.