Document ID: ./input/supremecourt_opinions/opinions/21pdf/21-248_4fc5.pdf
Page Number: 17.0

Cite as:  597 U. S. ____ (2022) 

13 

Opinion of the Court 

does not necessarily and always capture all relevant state 
interests.  Instead  and  as  we  have  seen,  where  a  State 
chooses to divide its sovereign authority among different of-
ficials and authorize their participation in a suit challeng-
ing  state  law,  a  full  consideration  of  the  State’s  practical
interests  may  require  the  involvement  of  different  voices
with different perspectives.  To hold otherwise would risk 
allowing a private plaintiff to pick its preferred defendants 
and potentially silence those whom the State deems essen-
tial to a fair understanding of its interests. 

B 
The only remaining question we face concerns adequacy
of representation.  Interpreting Rule 24(a)(2), lower courts
have adopted a variety of tests for evaluating whether an 
existing  defendant  already  “adequately  represent[s]”  the 
same interests a proposed intervenor seeks to vindicate.  In 
this case, both the District Court and the en banc Court of 
Appeals applied a “presumption” that the Board adequately
represented the legislative leaders’ interests and held that 
the leaders could not overcome this presumption.  999 F. 3d, 
at 934; Cooper, 332 F. R. D., at 171. 

Once more, we cannot agree.  As an initial matter, Rule 
24(a)(2) promises intervention to those who bear an interest 
that may be practically impaired or impeded “unless exist-
ing  parties  adequately  represent  that  interest.”    In  some 
cases, too, this Court has described the Rule’s test as pre-
senting  proposed  intervenors  with  only  a  minimal  chal-
lenge.

Take Trbovich v. Mine Workers, in which this Court ad-
dressed a request to intervene by a private party who as-
serted a related interest to that of an existing government 
party.  404 U. S. 528 (1972).  There, the Secretary of Labor 
sued to set aside a union election.  The same union member 
who  filed  the  administrative  complaint  that  triggered  the 
Secretary’s suit sought to intervene under Rule 24(a).  Id.,