Washington (CNN) Senate Majority Leader Mitch McConnell called Sen. Cory Booker's move Thursday to break Senate rules and release confidential emails traded by Brett Kavanaugh, President Donald Trump's Supreme Court nominee, "unusual behavior," and discussed a potential ethics investigation Friday.

"When you break the Senate rules, it's something the Ethics Committee could take a look at. And that would be up to them to decide," McConnell told conservative radio host Hugh Hewitt in an MSNBC interview. "They have an obligation to look into violations of the Senate rules, and it wouldn't surprise me if they did."

Booker's announcement on Thursday, made in front of cameras and with an air of theatrics, was slammed as a stunt by Republicans who pointed out that the documents in question had already been cleared for public release.

But Booker continued throughout the day Thursday to release documents on Twitter -- some of which appeared to show Kavanaugh's personal views on the protection of religious interests -- that were confirmed by the Judiciary Committee chairman, Republican Sen. Chuck Grassley of Iowa, to still be considered "committee confidential."

Booker, considered to be a potential 2020 presidential candidate, was one of a handful of Democrats who generated headlines for bold moves at the hearing.

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