Document ID: ./input/supremecourt_opinions/opinions/06pdf/05-1120.pdf
Page Number: 30.0

24 

MASSACHUSETTS v. EPA 

Opinion of the Court

V 

The  scope  of  our  review  of  the  merits  of  the  statutory 
issues is narrow.  As we have repeated time and again, an
agency has broad discretion to choose how best to marshal 
its  limited  resources  and  personnel  to  carry  out  its  dele-
gated  responsibilities.  See  Chevron  U. S. A.  Inc.  v.  Natu-
ral Resources Defense Council, Inc., 467 U. S. 837, 842–845 
(1984).  That  discretion  is  at  its  height  when  the  agency 
decides not to bring an enforcement action.  Therefore, in 
Heckler  v.  Chaney,  470  U. S.  821  (1985),  we  held  that  an
agency’s refusal to initiate enforcement proceedings is not 
ordinarily  subject  to  judicial  review.    Some  debate  re-
mains,  however,  as  to  the  rigor  with  which  we  review  an 
agency’s denial of a petition for rulemaking. 

There are key differences between a denial of a petition 
for rulemaking and an agency’s decision not to initiate an 
enforcement action.  See American Horse Protection Assn., 
Inc. v. Lyng, 812 F. 2d 1, 3–4 (CADC 1987).  In contrast to 
nonenforcement  decisions,  agency  refusals  to  initiate
rulemaking “are less frequent, more apt to involve legal as 
opposed to factual analysis, and subject to special formali-
—————— 

country.    Rather  than  a  limited  group  of  persons  who  used  a  pictur-
esque  valley  in  California,  all  persons  who  utilize  the  scenic  resources
of  the  country,  and  indeed  all  who  breathe  its  air,  could  claim  harm 
similar to that alleged by the environmental groups here.  But we have 
already made it clear that standing is not to be denied simply because 
many people suffer the same injury.  Indeed some of the cases on which 
we  relied  in  Sierra  Club  demonstrated  the  patent  fact  that  persons
across  the  Nation  could  be  adversely  affected  by  major  governmental 
actions.    To  deny  standing  to  persons  who  are  in  fact  injured  simply 
because many others are also injured, would mean that the most injuri-
ous and widespread Government actions could be questioned by nobody. 
We cannot accept that conclusion.”  Ibid. (citations omitted and empha-
sis added). 
It  is  moreover  quite  wrong  to  analogize  the  legal  claim  advanced  by
Massachusetts and the other public and private entities who challenge 
EPA’s  parsimonious  construction  of  the  Clean  Air  Act  to  a  mere  “law-
yer’s game.”  See post, at 14.