Chevron U.S.A., Inc. v. NRDC (1984)
Chevron v. NRDC (1984) established the modern doctrine of judicial deference to administrative agencies, profoundly shaping U.S. environmental and regulatory law. The Supreme Court’s decision allowed agencies like EPA to interpret ambiguous statutes, provided their interpretation was reasonable. In June 2024, this doctrine was overruled, fundamentally changing federal regulatory review[1][3][5][6][8][11].
Key Events Timeline
  • 1977: Congress amends the Clean Air Act, requiring nonattainment states to regulate "new or modified major stationary sources" of air pollution[1][3][5].
  • 1981: EPA introduces the "bubble policy," allowing plantwide emissions trading for permit purposes[1][5].
  • 1982: NRDC challenges the EPA rule; D.C. Circuit strikes down the bubble policy[1][3][5].
  • Feb 29, 1984: Supreme Court hears oral arguments[1][3][7].
  • June 25, 1984: Supreme Court upholds EPA’s interpretation, creating the Chevron doctrine[1][2][3][5][7].
  • 1984-2024: Chevron cited in over 18,000 federal decisions, shaping environmental, health, and financial regulation[4][5][8][11].
  • June 2024: Chevron overruled in Loper Bright v. Raimondo; courts no longer defer to agency interpretations just because a statute is ambiguous[4][6].
Federal Cases Citing Chevron, 1984-2024
0 500 1000 1700 1984 1990 1996 2002 2008 2014 2024 Chevron Citations (Federal)
Chevron was cited in over 18,000 federal cases from 1984-2024, peaking in the late 1990s and declining after 2015 as the Supreme Court narrowed its scope[4][5][8][11].
EPA Major Rule Challenges: Outcomes by Era
0% 25% 50% 75% Pre-Chevron Chevron Era Post-Chevron 48% 62% 41%
In the Chevron era, about 62% of major EPA rules challenged in federal court were upheld, compared to 48% before Chevron and 41% projected after its overruling[4][5][8][11].
Clean Air Act: U.S. Air Quality Progress (1980-2024)
YearGDP (T$)Population (M)SO₂ Emissions (Mt)NOₓ Emissions (Mt)PM₂.₅ (μg/m³)Ozone (ppb)
19802.822723.522.621.088
200010.328211.216.214.572
202021.53313.78.68.965
2024 (proj.)24.23353.48.18.763
Result: U.S. GDP and population grew sharply, while major air pollutants fell 60–85% since 1980, showing the regulatory and technological impact of the Clean Air Act and EPA policy[4][5][8][11].
Chevron Two-Step Test
Step 1: Has Congress spoken directly to the issue?
If congressional intent is clear, both court and agency must follow it. If ambiguous, proceed to Step 2[1][2][3][5].
Step 2: Is the agency’s interpretation permissible?
If the statute is ambiguous, courts defer to the agency’s reasonable interpretation, unless it is arbitrary, capricious, or manifestly contrary to the statute[1][2][3][5].
Implications for Environmental & Administrative Law
AreaChevron Era (1984-2024)Post-Chevron Era (2024- )
Judicial ReviewCourts defer to agency interpretations if reasonable and statute is ambiguousCourts independently interpret statutes, no deference to agency on ambiguity
Agency PowerAgencies had broad authority to interpret ambiguous statutesAgency power is curtailed; courts have final say on statutory meaning
Regulatory UncertaintyGreater predictability for agencies, less for regulated partiesPotential for more litigation and variability as courts may reach different interpretations
Environmental PolicyEPA could adapt statutes to new scientific or economic realitiesAgencies may face more legal challenges; major policy shifts require explicit Congressional authorization
Why Chevron Matters
Chevron deference shaped U.S. environmental policy for four decades, allowing agencies to fill statutory gaps and respond to evolving science. Its overruling in 2024 shifts interpretive power to the judiciary, likely increasing litigation, reducing regulatory flexibility, and requiring Congress to legislate with greater specificity. This change will impact climate, air, water, and health regulation for years to come[1][3][5][6][8].
Key citation: Chevron U.S.A., Inc. v. NRDC, 467 U.S. 837 (1984); Loper Bright Enterprises v. Raimondo, 601 U.S. ___ (2024).

Chevron U.S.A., Inc. v. NRDC (1984)