A group of Republican senators has written a letter to the U.S. Attorney General to stifle any future federal inquiries concerning climate change, claiming it violates the First Amendment rights of corporations like ExxonMobil, which suppressed its research into the phenomenon for several decades, according to an explosive report from Inside Climate News last September.

A group of Democratic senators has since responded with their own letter, asking the Attorney General to stay the course.

The first letter, signed by Republicans Ted Cruz, Jeff Sessions, Mike Lee, David Perdue, and David Vitter, accused the attorney general of suppressing debate on the validity of climate change, a violation of the First Amendment rights of corporations who have continued to question the validity of climate change.

Privately-funded scientific research can be actively misrepresented, they argue, even despite the global implications of doing so. It’s not fraud, it’s free speech!

“These actions provide disturbing confirmation that government officials at all levels are threatening to wield the sword of law enforcement to silence debate on climate change,” the letter, addressed to Attorney General Loretta Lynch, reads. “As you well know, initiating criminal prosecution for a private entity’s opinions on climate change is a blatant violation of the First Amendment and an abuse of power that rises to the level of prosecutorial misconduct.”

“Threatening prosecution of those who dare to challenge the most outlandish scaremongering by climate activists strikes at the very heart of the Free Speech protections on which this nation was founded,” said Lee, one of the senators who signed the letter, in a statement that appeared on Cruz’s Senate page.

Senators Bernie Sanders, Elizabeth Warren, Jeff Merkley, and Sheldon Whitehouse, some of the most liberal Democrats in the chamber, shot back with their own statement claiming that companies like Exxon committed fraud, which isn’t protected as free speech under the First Amendment, when suppressing the findings of its own scientists on the effects of fossils fuels.

“We write today to urge that you view the Republican Senators’ May 25 letter as Exhibit A among the reasons why the Department of Justice should take a full and honest look at possible fraud in the fossil fuel industry’s climate denial operation,” read the Democratic senators’ response. “It has always been and remains good law that fraud is not protected by the First Amendment. It would be a sorry world in which corporations engaged in fraud could pull the screen of the First Amendment over any investigation of their fraud.”

The senators said that their Republican counterparts were using tactics once used by the tobacco industry and its supporters to suppress scientific scrutiny of the harmful effects of cigarettes on humans.

“The Republican Senators’ letter reprises the tobacco lawsuit’s own early history of efforts from Congress to discourage or interfere with that lawsuit in order to protect the tobacco industry,” continued the letter. “The Republican Senators’ letter also reprises arguments made in the press against bringing the tobacco lawsuit, and made in court against that lawsuit: to wit, that the First Amendment should prevent the investigation or determine the litigation. This argument was soundly rejected by the Department, and then by Judge Kessler, and then by the United States D.C. Circuit Court of Appeals.”

It’s ironic that the party of climate change deniers is demanding that their side be given the freedom of speech to air their politically motivated, unscientific opinions on climate change while consistently opposing any discussion of the real effects by anyone who doesn’t agree with them. Last year, aided in part by Cruz, Republicans claimed that NASA was wasting money monitoring weather patterns that have revealed already the real effects of climate change. “The core function of NASA is to explore space,” said the Texas senator. “NASA in the current environment has lost its full focus on that core mission.”

He was predictably annoyed that NASA was actively educating the public about the realities of climate change and sharing the data it collected with the global scientific community.

While Republicans may want to continue to question and deny the scientific validity of climate change, even their bankrollers are beginning to come around to the reality that fossil fuels are shifting the planet’s weather patterns and causing extreme weather to occur more regularly. On Wednesday, ExxonMobil, the largest publicly traded energy company in the world, voted to make it easier to elect climate change advocates to the company’s board of directors in a vote approved by 62 percent of the company’s shareholders.

“We are not ignoring the risk that is out there,” said Exxon CEO Rex Tillerson following a shareholder meeting in Dallas, when pressed by one shareholder about climate science. “I don’t think we see it all that differently. Our differences are in how we’re going to address it.”

That wasn’t the case for decades, when Exxon hid the scientific evidence of anthropogenic climate change. Now, Republicans want to protect the rights of other corporations to lie about the potentially catastrophic implications of their private scientific research.