Document ID: ./input/supremecourt_opinions/opinions/21pdf/20-601_bq7c.pdf
Page Number: 13

Cite as:  595 U. S. ____ (2022) 

9 

Opinion of the Court 

in  any  “court  of  the  United  States”  and  neither  the  State 
nor  any  state  agency  or  officer  is  a  party,  the  court  must 
notify the state attorney general, and the State must be al-
lowed to intervene.  See also Fed. Rule Civ. Proc. 24(a)(1).  
Even if this provision is not directly applicable in this case 
because the secretary for Health and Family Services was 
still a party when the intervention motion was filed, it nev-
ertheless reflects the  weighty  interest  that  a  State  has  in 
protecting  its  own  laws.    The  way  in  which  Kentucky  di-
vides executive authority and the unusual course that this 
litigation  took  should  not  obscure  the  important  constitu-
tional consideration at stake.4 
  Resolution of a motion for permissive intervention is com-
mitted to the discretion of the court before which interven-
tion  is  sought, see  Automobile  Workers,  382  U. S.,  at  217,  
n. 10; Fed. Rule Civ. Proc. 24(b)(1)(a).  But a court fails to 
exercise its discretion soundly when it “base[s] its ruling on 
an erroneous view of the law,” Cooter & Gell v. Hartmarx 
Corp., 496 U. S. 384, 405 (1990), and that is what happened 
here.    The  Sixth  Circuit  panel  failed  to  account  for  the 
strength of the Kentucky attorney general’s interest in tak-
ing up the defense of HB 454 when the secretary for Health 
and Family Services elected to acquiesce.5 
—————— 

4 JUSTICE KAGAN argues that the Court need not address the constitu-
tional basis for Kentucky’s interest in the defense of its laws, but that 
interest was a primary focus of the briefs and oral argument.  And in-
deed, JUSTICE KAGAN  agrees that  “a  State  has  a significant  interest  in 
enforcing  its  own  laws.”    Post,  at  5  (opinion  concurring  in  judgment).  
Such  an  interest  depends  on  States’  status  as  “separate  sovereigns.”  
Maine v. Taylor, 477 U. S. 131, 137 (1986). 

5 The dissent argues that the Court of Appeals did not abuse its discre-
tion by denying the attorney general’s intervention motion because his 
predecessor in office had argued that he had no interest in the litigation.  
Post, at 5–6.  The dissent argues that we should hold the attorney general 
to  that  representation.    But  the  Court  of  Appeals  did  not  rely  on  this 
argument, and  for  good  reason.   The  attorney  general  was  sued  in  his 
role as a state official who could enforce HB 454, and the attorney general 
had  disclaimed  any  such  enforcement  authority.    See  Ex  parte  Young,