Document ID: ./input/supremecourt_opinions/opinions/22pdf/21-1484_aplc.pdf
Page Number: 34.0

Cite as:  599 U. S. ____ (2023) 

13 

GORSUCH, J., dissenting 

Air France v. Saks, 470 U. S. 392, 399 (1985).  All with an 
eye to ensuring both sides receive the “benefit of their bar-
gain.”  Mobil Oil Exploration & Producing Southeast, Inc. 
v. United States, 530 U. S. 604, 621 (2000). 

That  exercise  entails  the  application  of  familiar  princi-
ples of contract interpretation.  Those principles include an
implied covenant of “the utmost good faith” and fair dealing 
between the parties.  Sullivan v. Kidd, 254 U. S. 433, 439 
(1921).  They include the doctrine of contra proferentem— 
the principle that any uncertainty in a contract should be
construed against the drafting party.  See Lamps Plus, Inc. 
v. Varela, 587 U. S. ___, ___–___ (2019) (slip op., at 9–10);
see  also  1  Oppenheim’s  International  Law  1279  (R.  Jen-
nings & A. Watts eds., 9th ed. 1992).  And they include the
doctrine of unilateral mistake—the notion that, if two par-
ties understand a key provision differently, the controlling 
meaning is the one held by the party that could not have 
anticipated  the  different  meaning  attached  by  the  other.
See Restatement (Second) of Contracts §201(2) (1979).

Still other doctrines impose a “higher degree of scrutiny” 
on contracts made between parties sharing a fiduciary re-
lationship, given the risk the fiduciary will (intentionally or 
otherwise) “misuse” its position of trust.  28 R. Lord, Willis-
ton  on  Contracts  §71:53,  p.  617  (4th  ed.  2020).    When  it 
comes to the United States, such fiduciary duties must, of 
course, come from positive law, “not the atmosphere.”  Haa-
land v. Brackeen, 599 U. S. ___, ___–___ (2023) (slip op., at 
11–12).  But the United States has, through “acts of Con-
gress” and other affirmative conduct, voluntarily assumed
certain specific fiduciary duties to the Tribes.  Seminole Na-
tion v. United States, 316 U. S. 286, 287, 297 (1942).  That 
raises the specter of undue influence—especially since, in
many negotiations with the Tribes, the United States alone 
had “representatives skilled in diplomacy” who were “mas-
ters  of  [its]  written  language,”  who  fully  “underst[ood]
the . . . technical estates known to [its] law,” and who were