Story highlights On Wednesday Sen. McCain publicly accused Sen. Paul of "working for Vladimir Putin" on the Senate floor

Do these accusations violate the Senate Rule 19 against imputing another senator?

Sen. Elizabeth Warren was halted from speaking earlier this year on those grounds

(CNN) Sen. John McCain accused Sen. Rand Paul of "working for Vladimir Putin" on the Senate floor Wednesday, leading some to wonder if the Arizona Republican had violated Rule 19, a Senate regulation evoked earlier this year when one senator imputes the honor of another.

McCain's comments came after Paul objected to a resolution that would allow Montenegro to join the NATO alliance. McCain responded by lobbing accusations at his fellow GOP senator multiple times, both before and after Paul objected to the vote, though the Kentucky senator did not add additional defense Wednesday.

Pointedly singling out the "gentleman from Kentucky," McCain said those who object "are now carrying out the desires and ambitions of Vladimir Putin."

When Paul formally objected, McCain reiterated his opinion.

"The senator from Kentucky is now working for Vladimir Putin," he said.

Read More