WASHINGTON -(Dow Jones)- Environmentalists scorned the Environmental Protection Agency's final decision Friday that rejects California's request to regulate greenhouse gas emissions from vehicles.

The decision, a controversial ruling made by EPA Administrator Stephen Johnson against the advice of senior agency staff, has been branded by many Democratic lawmakers and environmentalists as politically motivated and followed strong lobbying pressure from auto manufacturers.

William Becker, executive director of the National Association of Clean Air Agencies, called Johnson's decision "a direct attack on the rights of states to protect the health and welfare of its citizens."

"Never before has EPA denied California and other states the ability to enforce more stringent vehicle emissions standards," Becker said.

David Doniger, a spokesman for the Natural Resources Defense Council, an environmental group, added, "California has the widest variety of severe impacts from global warming." Even if the impact of global warming is no different in California than in other states, Doniger said, the federal Clean Air Act is designed to allow other states to adopt California's standards once the state gets permission from the EPA.

Vickie Patton, deputy general counsel for the Environmental Defense Fund, said, "California's compelling and extraordinary need to address global warming is being directly undermined by EPA's extraordinarily reckless refusal to follow the law and the science."

Legislators, environmental lawyers and auto industry lobbyists had been eagerly awaiting the publication of the EPA's formal "scientific rationale" for denying California permission to regulate greenhouse gases. At least 19 other states were anxiously awaiting the EPA decision on the request - originally made in late 2005 - so that if it was approved, they could adopt similar rules.

Until now, the EPA hadn't published any data or research to back up Johnson's announcement on Dec. 19 that California lacks "compelling and extraordinary conditions" that warrant allowing it to regulate greenhouse gases from automobiles independently from the federal government.

The California Air Resources Board requested the waiver from the federal government believing the proposed aggressive emission regulations were necessary to counter global climate change. The state said it would suffer damaging economic and environmental effects if greenhouse gases weren't curbed.

In the final decision, Johnson says California's law only allows it to publish emission standards for vehicles to address pollution problems that are local or regional. And so, he writes, "I do not believe (the law) was intended to allow California to promulgate state standards for emissions from new motor vehicles designed to address global climate change."

EPA Decision Also Under Scrutiny In Congress

Johnson is also coming under fire in two congressional investigations into his decision, one conducted by the Senate Environment and Public Works Committee and the other by the House Oversight and Government Reform Committee.

Chairwoman of the Senate environment panel Barbara Boxer, D-Calif., said earlier this week that she would be working together with Rep. Henry Waxman, D- Calif., chairman of the House oversight panel, to subpoena emails and records of discussions between the executive branch and the EPA.

"Those documents will be subpoenaed," Boxer said at an EPA budget hearing. " The law requires Mr. Johnson to turn over this information....The fact is that this is not privileged information...and we want to know who influenced your decision."

On Friday, Sen. Dianne Feinstein, D-Calif., chairwoman of the Senate Appropriations Subcommittee on the Interior, Environment and Related Agencies, called for the Government Accountability Office and the EPA's Inspector General also to investigate the decision.

Johnson has said he received a "wide range of recommendations" from his staff on how to respond to California's petition. But internal EPA documents made public this week by Senate Democrats also show that several top EPA staffers supported California's request and tried to warn Johnson that a rejection could mean he would have to resign.

The EPA chief has also faced criticism for delaying the decision, waiting for a Supreme Court ruling that forced the agency to make a decision. In May last year, President George W. Bush directed the EPA to craft rules for greenhouse gas emissions from vehicles by the end of 2008, following an April Supreme Court decision that said the EPA has the authority to regulate the pollutant carbon dioxide.

Johnson has previously said his agency is also studying the impact of vehicle greenhouse gas regulations on stationary sources such as power generators, refiners and chemical plants.

Although federal regulation for greenhouse gases from vehicles might initially affect car manufacturers such as Ford Motor Co. (F), General Motors Co. (GM) and Chrysler LLC, ultimately, EPA carbon dioxide rules could also hit utilities such as American Electric Power Co. (AEP) and TXU Energy,refiners such as Tesoro Corp. (TSO) and Valero Energy Corp. (VLO) and most chemical companies, oil companies and other major greenhouse gas emitters.

Johnson was careful to note in his rationale that while he recognizes global warming is a serious challenge, the document doesn't reflect a judgment of whether greenhouse gas emissions cause or contribute to air pollution "which may reasonably be anticipated to endanger public health or welfare." Such a determination - which the EPA says it is continuing to evaluate - would have implications on stationary sources too.