Washington (CNN) Democratic Rep. Kathleen Rice of New York, a former federal prosecutor, has asked the House Ethics Committee to investigate a statement Republican Rep. Matt Gaetz made about Michael Cohen, saying that she believes the GOP lawmaker's comments could rise to the level of witness tampering and intimidation.

Gaetz, a close ally to the President, tweeted at Cohen on Tuesday, saying, "Do your wife & father-in-law know about your girlfriends? Maybe tonight would be a good time for that chat. I wonder if she'll remain faithful when you're in prison. She's about to learn a lot."

The statement -- which came the day before Cohen, Trump's former personal lawyer, testified publicly before Congress -- sparked an immediate backlash, including from some House Democrats who suggested that it amounted to witness intimidation.

In a letter sent to the chairman and top Republican on the House Ethics Committee on Tuesday, Rice asks for the panel to "immediately open an investigation" into the statement.

"As a former District Attorney and federal prosecutor, I believe this statement is in violation of 18 U.S. Code § 1512, which clearly defines witness tampering and intimidation," the Democratic lawmaker wrote. "According to the Department of Justice (DOJ), this statue applies to proceedings before Congress."

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