The thought that practically the entire Republican Senate caucus could be charged with violating the Logan Act is hard to take seriously, even after Sen. Tom Cotton (R-Ark.) and 46 of his colleagues penned a letter to the Iranian government on Monday with the intent of derailing President Obama’s ongoing nuclear negotiations with that country. But the State Department hasn’t ruled it out.

“I’m not aware of any conversations within the United States government regarding whether Senator Cotton and the other signatories violated the Logan Act,” spokeswoman Jen Psaki told reporters on Tuesday.

“This is a legal act and I’d certainly defer to others on that,” she added.

Although stopping short of saying Republican Senators had broken the law, Psaki did say their letter put the country at risk.

“We believe it’s harmful to America’s national security for anybody to insert themselves into the middle of a very sensitive negotiation.”

Her tone contrasts with that of Sen. Chris Murphy (D-Conn.), who, when asked the same question on Monday night, laughed off the idea that Republican Senators broke the law.

“I don’t buy that,” he said responding to a question from MSNBC host Chris Hayes.

“I think it’s Certainly within the bounds of Congress’ legal ability in order to send an open letter to the Iranian leadership, as they did.”

The Logan Act bars any unauthorized US citizens from engaging in negotiations with foreign government to influence that government in relation to “disputes or controversies with the United States, or to defeat the measures of the United States.”

It was signed into law in 1799 by President John Adams.

The White House has reacted to the letter with indignation, but hasn’t alleged any criminal wrongdoing was committed by its signatories.

“It’s somewhat ironic to see some members of Congress wanting to make common cause with the hardliners in Iran,” President Obama told reporters on Monday.

Vice President Joe Biden described the “Dear John” as unprecedented.

“This letter sends a highly misleading signal to friend and foe alike that that our Commander-in-Chief cannot deliver on America’s commitments — a message that is as false as it is dangerous,” he said in a statement.

Many Republican lawmakers have also distanced themselves from the letter.

Rep. Peter King (R-N.Y.) told reporters on Tuesday that, although he agreed with the “tone” of the letter and doesn’t agree with president’s approach, he said, “quite frankly,” he wouldn’t “go public with it to a foreign government.” Senate Foreign Relations Committee chair Bob Corker (R-Tenn.) also declined to attach his name to the letter.

UPDATE: A previous version of this article claimed that Sens. John McCain (R-Ariz.) and Lindsey Graham (R-S.C.) had not signed on to Cotton’s letter. They did.