Document ID: ./input/supremecourt_opinions/opinions/23pdf/22-451_7m58.pdf
Page Number: 88.0

Cite as:  603 U. S. ____ (2024) 

7 

KAGAN, J., dissenting 

In each case, a statutory phrase has more than one reason-
able reading.  And Congress has not chosen among them: It 
has  not,  in  any  real-world  sense,  “fixed”  the  “single,  best
meaning” at “the time of enactment” (to use the majority’s
phrase).  Ante, at 22.  A question thus arises: Who decides 
which of the possible readings should govern? 

This Court has long thought that the choice should usu-
ally fall to agencies, with courts broadly deferring to their
judgments.  For the last 40 years, that doctrine has gone by 
the name of Chevron deference, after the 1984 decision that 
formalized and canonized it.  In Chevron, the Court set out 
a simple two-part framework for reviewing an agency’s in-
terpretation of a statute that it administers.  First, the re-
viewing  court  must  determine  whether  Congress  has  “di-
rectly spoken to the precise question at issue.”  467 U. S., at 
842.  That inquiry is rigorous: A court must exhaust all the 
“traditional tools of statutory construction” to divine statu-
tory meaning.  Id., at 843, n. 9.  And when it can find that 
meaning—a “single right answer”—that is “the end of the 
matter”: The court cannot defer because it “must give effect 
to the unambiguously expressed intent of Congress.”  Kisor, 
588 U. S., at 575 (opinion of the Court); Chevron, 467 U. S., 
at  842–843.  But  if  the  court,  after  using  its  whole  legal 
toolkit, concludes that “the statute is silent or ambiguous 
with respect to the specific issue” in dispute—for any of the 
not-uncommon  reasons  discussed  above—then  the  court 
must cede the primary interpretive role.  Ibid.; see supra, 
at 4–5.  At that second step, the court asks only whether the
agency  construction  is  within  the  sphere  of  “reasonable” 
readings.  Chevron, 467 U. S., at 844.  If it is, the agency’s
interpretation of the statute that it every day implements
will control. 

That rule, the Court has long explained, rests on a pre-
sumption  about  legislative  intent—about  what  Congress
wants when a statute it has charged an agency with imple-
menting contains an ambiguity or a gap.  See id., at 843–