In its Massachusetts vs. EPA ruling issued yesterday, the Supreme Court found that the Clean Air Act does, in fact authorize EPA to regulate carbon dioxide emissions from vehicles. (For background on the case, see Justin Pidot’s post on Gristmill.) The ruling states:

While the Congresses that drafted §202(a)(1) might not have appreciated the possibility that burning fossil fuels could lead to global warming, they did understand that without regulatory flexibility, changing circumstances and scientific developments would soon render the Clean Air Act obsolete. The broad language of §202(a)(1) reflects an intentional effort to confer forestall such obsolescence.

The majority opinion (PDF), authored by Justice Stevens, conveyed that the five justices were unimpressed by the administration’s excuses for why EPA shouldn’t be regulating these emissions (or why the court shouldn’t be deciding whether it could). Many of those, it happens, are the same excuses the administration keeps trotting out to defend its inaction on climate change as a whole (emphasis added in all):

Excuse 1: We can’t solve the entire global warming problem just by tinkering with tailpipe emissions – and growing emissions from China and India would offset our improvements, anway – so, really, let’s not bother.

Ruling:

But EPA overstates its case. Its argument rests on the erroneous assumption that a small incremental step, because it is incremental, can never be attacked in a federal judicial forum. Yet accepting that premise would doom most challenges to regulatory action. Agencies, like legislatures, do not generally resolve massive problems in one fell regulatory swoop. […]

And reducing domestic automobile emissions is hardly a tentative step. Even leaving aside the other greenhouse gases, the United States transportation sector emits an
enormous quantity of carbon dioxide into the atmosphere—according to the MacCracken affidavit, more than 1.7 billion metric tons in 1999 alone. ¶30, Stdg. App. 219.
That accounts for more than 6% of worldwide carbon dioxide emissions. […]

Because of the enormity of the potential consequences associated with man-made climate change, the fact that the effectiveness of a remedy might be delayed during the (relatively short) time it takes for a new motor-vehicle fleet to replace an older one is essentially irrelevant. Nor is it dispositive that developing countries such as China and India are poised to increase greenhouse gas emissions substantially over the next century: A reduction in domestic emissions would slow the pace of global emissions increases, no matter what happens elsewhere.

Excuse 2: We’re already addressing climate change so effectively – there’s no need for any additional regulation! Never mind about that whole Clean Air Act thing …

Ruling:

EPA has refused to comply with this clear statutory command. Instead, it has offered a laundry list of reasons not to regulate. For example, EPA said that a number of voluntary executive branch programs already provide an effective response to the threat of global warming, 68 Fed. Reg. 52932, that regulating greenhouse gases might impair the President’s ability to negotiate with “key developing nations” to reduce emissions, id., at 52931, and that curtailing motor-vehicle emissions would reflect “an inefficient, piecemeal approach to address the climate change issue,” ibid.

Although we have neither the expertise nor the authority to evaluate these policy judgments, it is evident they have nothing to do with whether greenhouse gas emissions contribute to climate change. Still less do they amount to a reasoned justification for declining to form a scientific judgment. In particular, while the President has broad authority in foreign affairs, that authority does not extend to the refusal to execute domestic laws. In the Global Climate Protection Act of 1987, Congress authorized the State Department—not EPA—to formulate United States foreign policy with reference to environmental matters relating to climate. See §1103(c), 101 Stat. 1409. EPA has made no showing that it issued the ruling in question here after consultation with the State Department. Congress did direct EPA to consult with other agencies in the formulation of its policies and rules, but the State Department is absent from that list. §1103(b).

And, of course, everyone’s favorite – that classic excuse that Philip Morris elevated to an art form: The science is still too uncertain to allow us to act.

Ruling:

Nor can EPA avoid its statutory obligation by noting the uncertainty surrounding various features of climate change and concluding that it would therefore be better not to regulate at this time. See 68 Fed. Reg. 52930–52931. If the scientific uncertainty is so profound that it precludes EPA from making a reasoned judgment as to whether greenhouse gases contribute to global warming, EPA must say so. That EPA would prefer not to regulate greenhouse gases because of some residual uncertainty—which, contrary to JUSTICE SCALIA’s apparent belief, post, at 5–8, is in fact all that it said, see 68 Fed. Reg. 52929 (“We do not believe . . . that it would be either effective or appropriatefor EPA to establish [greenhouse gas] standards for motor vehicles at this time” (emphasis added))—is irrelevant. The statutory question is whether sufficient information exists to make an endangerment finding.

Oh, and speaking of Justice Scalia: He, Roberts, Thomas, and Alito were the dissenters. Who’d have guessed?

David Roberts at Gristmill sums up what this means for the Bush administration (and provides a bunch of links to other blogger reactions):

Bush's isolation on this issue is now total. No one stands with him -- not Congress, not the business community, not the religious community, not the public at large, not the courts. Only James Inhofe. That's a grim assessment indeed.

Will the Bush administration keep using the same excuses, even though the points they make have been refuted by the Supreme Court?