Former Vice President Al Gore and several liberal attorneys general are stepping up their attack on companies and organizations that question global warming, using "McCarthy-style tactics" to criminalize critics and their supporters, according to one target.

The well-respected Washington-based Competitive Enterprise Institute said Friday that it has been hit with a subpoena for climate research documents and even donor lists from 1997-2007 from one of the attorneys in the Gore group. CEI was given three weeks to provide the 20-year-old documents.

It is the latest move by Gore and his legal partners to go after companies and groups they feel have sought to cloud their belief that global warming is real and a threat to the world's health.

Two weeks ago, Gore and attorneys general From California, Connecticut, District Of Columbia, Illinois, Iowa, Maine, Maryland, Massachusetts, Minnesota, New Mexico, New York, Oregon, Rhode Island, Virginia, Vermont, Washington State and the U.S. Virgin Islands created their coalition to go after climate change critics.

"We cannot continue to allow the fossil fuel industry or any industry to treat our atmosphere like an open sewer or mislead the public about the impact they have on the health of our people and the health of our planet. Attorneys General and law enforcement officials around the country have long held a vital role in ensuring that the progress we have made to solve the climate crisis is not only protected, but advanced. The first-of-its-kind coalition announced today is another key step on the path to a sustainable, clean-energy future," Gore said at the time.

CEI, which said it promotes "sound climate change policy," is fighting the subpoena from Virgin Island Attorney General Claude E. Walker and what it described as an intimidation campaign.

"CEI will vigorously fight to quash this subpoena. It is an affront to our First Amendment rights of free speech and association for Attorney General Walker to bring such intimidating demands against a nonprofit group," said CEI general counsel Sam Kazman in a statement. "If Walker and his allies succeed, the real victims will be all Americans, whose access to affordable energy will be hit by one costly regulation after another, while scientific and policy debates are wiped out one subpoena at a time."

The fight is nothing new for CEI, which said in a statement to Secrets:

"CEI has long been a champion of sound climate change policy, and opposed previous attempts to use McCarthy-style tactics by officials aiming to limit discussions between nonprofit policy groups and the private sector regarding federal policies. CEI is being represented in this matter by attorneys Andrew M. Grossman and David B. Rivkin, Jr., who recently founded the Free Speech in Science Project to defend First Amendment rights against government abuses."

Paul Bedard, the Washington Examiner's "Washington Secrets" columnist, can be contacted at pbedard@washingtonexaminer.com