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Page Number: 14.0

8 

MASSACHUSETTS v. EPA 

Opinion of the Court 

gases are accumulating in Earth’s atmosphere as a result
of human activities, causing surface air temperatures and 
subsurface ocean temperatures to rise.  Temperatures are,
in fact, rising.”  NRC Report 1. 

On September 8, 2003, EPA entered an order denying the
rulemaking petition.  68 Fed. Reg. 52922.  The agency gave
two reasons for its decision: (1) that contrary to the opin-
ions of its former general counsels, the Clean Air Act does
not  authorize  EPA  to  issue  mandatory  regulations  to 
address  global  climate  change,  see  id.,  at  52925–52929; 
and  (2)  that  even  if  the  agency  had  the  authority  to  set
greenhouse gas emission standards, it would be unwise to
do so at this time, id., at 52929–52931. 

In  concluding  that  it  lacked  statutory  authority  over 
greenhouse  gases,  EPA  observed  that  Congress  “was  well 
aware  of  the  global  climate  change  issue  when  it  last 
comprehensively  amended  the  [Clean  Air  Act]  in  1990,” 
yet  it  declined  to  adopt  a  proposed  amendment  establish-
ing binding emissions limitations.  Id., at 52926.  Congress
instead  chose  to  authorize  further  investigation  into  cli-
Ibid.  (citing  §§103(g)  and  602(e)  of  the 
mate  change. 
Clean Air Act Amendments of 1990, 104 Stat. 2652, 2703, 
42  U. S. C.  §§7403(g)(1)  and  7671a(e)).    EPA  further  rea-
soned that Congress’ “specially tailored solutions to global 
atmospheric issues,” 68 Fed. Reg. 52926—in particular, its 
1990  enactment  of  a  comprehensive  scheme  to  regulate 
pollutants that depleted the ozone layer, see Title VI, 104 
Stat.  2649,  42  U. S. C.  §§7671–7671q—counseled  against 
reading  the  general  authorization  of  §202(a)(1)  to  confer 
regulatory authority over greenhouse gases. 

EPA  stated  that  it  was  “urged  on  in  this  view”  by  this
Court’s  decision  in  FDA  v.  Brown  &  Williamson  Tobacco 
Corp.,  529  U. S.  120  (2000).    In  that  case,  relying  on  “to-
bacco[’s]  unique  political  history,”  id.,  at  159,  we  invali-
dated  the  Food  and  Drug  Administration’s  reliance  on  its 
general authority to regulate drugs as a basis for asserting