October Term 2006 · Docket 05-1120

Can states force the EPA to regulate car emissions?

Massachusetts and other states ask the Court to compel the EPA to set limits on vehicle greenhouse gases. The EPA argues Congress did not grant it that power.

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Massachusetts v. EPA
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Official Transcript

Verified source milestones

  1. — An official oral-argument transcript was verified.

The arguments, in order

This case may have been argued more than once. Each entry below uses that session's official transcript. Later arguments do not erase earlier ones.

  1. Argument 1 ·

    What happened at the argument

    Justice Scalia questioned the link between car emissions and state injury.

    Justice Kennedy asked if proving global warming is necessary for standing.

    The EPA argued Congress did not authorize greenhouse gas regulation.

    Read the official transcript for this argument · Official argument details

    Sources used for this argument breakdown

A citizen's guide to the whole case

What this case is about

This case tests whether the EPA must regulate carbon dioxide from cars. The states claim this pollution harms them. The agency says its law does not cover this issue.

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How the case got here

The Supreme Court heard oral argument in this case on November 29, 2006.

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What each side wants

Massachusetts wants the Court to order the EPA to set car emission limits.

The EPA wants the Court to dismiss the case for lack of standing.

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What each side says

Massachusetts argues the EPA has the legal duty to regulate vehicle emissions.

The EPA argues Congress did not grant it authority to regulate greenhouse gases.

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What the justices asked

Justice Scalia asked if only new cars would be affected by new rules.

Justice Kennedy asked if the Court must decide global warming to find injury.

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Why it matters

This dispute determines if the EPA controls vehicle pollution. It shapes federal environmental regulation power. It affects state climate protection efforts.

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What happens next

This article currently covers the argument record. Use the official docket link for later case activity.

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Official Court provenance

Official docket and case history · Official Supreme Court oral-argument detail page

Title and summary sources

Revision history

  1. Revision 1 · Official Transcript ·

    Correction: Rewritten to the concise citizen-facing editorial standard.

  2. Revision 2 · Official Transcript ·

    Correction: Migrated to the dated official Court activity contract without model use.

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