Document ID: ./input/supremecourt_opinions/opinions/23pdf/23-235_n7ip.pdf
Page Number: 15.0

Cite as:  602 U. S. ____ (2024) 

11 

Opinion of the Court 

links—that is, where it is not sufficiently predictable how 
third  parties  would  react  to  government  action  or  cause
downstream  injury  to  plaintiffs.  See  Allen,  468  U.  S.,  at 
757–759;  Simon,  426  U. S.,  at  41–46.  The  causation 
requirement also rules out attenuated links—that is, where 
the  government  action  is  so  far  removed  from  its  distant
(even if predictable) ripple effects that the plaintiffs cannot 
establish Article III standing.  See Allen, 468 U. S., at 757– 
759; cf. Department of Commerce, 588 U. S., at 768. 

The  causation  requirement  is  central  to  Article  III 
standing.  Like the injury in fact requirement, the causation
requirement screens out plaintiffs who were not injured by
the defendant’s action.  Without the causation requirement, 
courts  would  be  “virtually  continuing  monitors  of  the 
wisdom and soundness” of government action.  Allen, 468 
U. S., at 760 (quotation marks omitted). 

Determining  causation  in  cases  involving  suits  by
unregulated parties against the government is admittedly 
not a “mechanical exercise.”  Id., at 751.  That is because 
the causation inquiry can be heavily fact-dependent and a 
“question  of  degree,”  as  private  petitioner’s  counsel  aptly
described  it  here.  Tr.  of  Oral  Arg.  50.  Unfortunately,
applying the law of standing cannot be made easy, and that 
is particularly true for causation.  Just as causation in tort 
law can pose line-drawing difficulties, so too can causation 
in standing law when determining whether an unregulated 
party has standing.

That said, the “absence of precise definitions” has not left 
courts  entirely  “at  sea  in  applying  the  law  of  standing.” 
Allen,  468  U. S.,  at  751.    Like  “most  legal  notions,  the
standing concepts have gained considerable definition from
developing case law.”  Ibid.  As the Court has explained, in 
“many cases the standing question can be answered chiefly 
by comparing the allegations of the particular complaint to
those  made  in  prior  standing  cases.”    Id.,  at  751–752. 
Stated otherwise, assessing standing “in a particular case