House GOP leaders have launched an internal review into how someone secretly recorded and leaked audio of a private 2016 leadership meeting in which Majority Leader Kevin McCarthy (R-Calif.) jokes about how Russia is paying off President Trump.

Sources familiar with the review told The Hill that GOP leadership is currently researching what federal statutes or House rules could be applied to hold the leaker accountable. Speaker Paul Ryan (R-Wis.) has voiced concerns that more audio recordings of sensitive leadership discussions could be leaked.

Leaders are also trying to figure out whether the individual who recorded the meeting passed or sent the audio of the high-level, closed-door meeting to a foreign government or foreign agent. National security and foreign policy implications are being evaluated as well, sources said.

"I believe it is important that these questions get answered," said a GOP lawmaker familiar with leadership's review. "I suspect this is only going to become more and more common."

Leadership sources suspect the leaker is former CIA officer Evan McMullin, who attended the June 15 meeting in the Capitol in his capacity as a top policy aide to GOP Conference Chairwoman Cathy McMorris Rodgers (R-Wash.). Two months later, McMullin launched a long-shot, independent run for president - an ultimately unsuccessful bid to deny Trump the White House.

McMullin, who has continued to badger Trump on Twitter and during TV interviews, did not respond to a request for comment. But McMullin alluded to the leadership meeting and McCarthy's Trump-Russia remark in a New York Times op-ed published in February.

And in The Washington Post story that first detailed the leadership meeting, McMullin is quoted acknowledging that he was present and specifically recalled McCarthy's remark about Trump. Both Ryan and McCarthy have called the comment a poor attempt at humor.

"It's true that Majority Leader McCarthy said that he thought candidate Trump was on the Kremlin's payroll," McMullin told the Post. "Speaker Ryan was concerned about that leaking."

Audio recordings have caused Hill Republicans huge headaches this year. A liberal activist infiltrated and secretly recorded a closed-door discussion at the GOP retreat in Philadelphia where House and Senate Republicans openly fretted about the challenges of repealing ObamaCare. The Post, Times and Politico were leaked copies of the recording.

And just this week, moments after Montana House GOP candidate Greg Gianforte allegedly body slammed and punched reporter Ben Jacobs, an audio recording of the incident - captured by Jacobs's smartphone - was blasted out online and on social media.

Gianforte was elected anyway, but the story consumed an entire news cycle and Ryan and other Republicans on the Hill were forced to answer uncomfortable questions about whether they supported a man just charged with assault.

Ryan is no stranger to these types of embarrassing leaks. After all, his 2012 running mate, GOP presidential nominee Mitt Romney, was the target of one of the most damaging campaign leaks in political history: a video of Romney saying "47 percent" of Americans are dependent on government handouts and "believe that they are victims."

The ease with which someone can digitally record and transmit a conversation or discussion on a smartphone means this is now the new normal for politicians. And lawmakers on Capitol Hill say they are being more cautious about what they say in meetings - even if the doors are closed and they are among friends.

"Any meeting I go into, I assume it's going to be recorded and reported," Rep. Richard Hudson (R-N.C.), who is close to leadership, told The Hill. "There are no private meetings in this modern day and age."

Rep. Trent Franks (R-Ariz.), a member of the Judiciary and Armed Services committees, called the spate of recent audio leaks "the new reality."

"These incessant leaks are becoming so pernicious and corrosive to the success of government and the public's ability to trust in it," Franks told The Hill. "The leaks are becoming more dangerous than the substance of what is being leaked."

The June leadership meeting in the Speaker's office in the Capitol was an intimate one. The four top GOP leaders - Ryan, McCarthy, McMorris Rodgers and Majority Whip Steve Scalise (La.) - attended, along with a handful of their top aides.

Even if GOP leaders proved McMullin leaked the audio, it's not clear what actions they could take. Since he's not currently a House employee, McMullin cannot be fired and the House Ethics Committee does not have jurisdiction over former staffers or lawmakers.

Also, it appears the leaker would be protected by the District of Columbia's wiretapping law, which states that recording a telephone or in-person conversation is legal as long as one party agrees to it.

Asked whether there was an internal review or investigation underway, McCarthy referred questions to his office. McMorris Rodgers also declined to discuss the matter.

"I'm not ready to comment," she told The Hill.

AshLee Strong, a Ryan spokeswoman, also declined to comment on a possible internal review. When asked whether any outside intelligence agencies, including the FBI or CIA, have been asked to assist the Speaker's office, Strong replied, "There's no outside investigation."

In the leaked transcript of the June leadership meeting, Ryan and others discuss the Russian hacking of the Democratic National Committee, Russia's "propaganda war" and the country's interference in Ukraine.

"Russia is trying to turn Ukraine against itself," Ryan told the group.

"Yes," McMorris Rodgers agreed, "and that's ... it's sophisticated and it's, uh-"

"Maniacal," Ryan chimed in.

Ryan had just met with the Ukrainian Prime Minister Volodymyr Groysman earlier that day, and last week's Post story carried a Kiev, Ukraine, dateline. But GOP sources don't believe the Ukrainians had bugged Ryan's offices because they are frequently swept and nothing was found.

One possible scenario being looked at is that an individual recorded the meeting, then transmitted the audio to a source, who shared it with the Post reporter in Kiev.

Franks, a fervent Trump backer, said if the leaker cannot be prosecuted under the law, then that person should be politically ostracized. McMullin has publicly discussed running against longtime Sen. Orrin Hatch (R-Utah) or to replace Rep. Jason Chafftez (R-Utah), who is quitting Congress next month.

"When someone deliberately and maliciously records someone to undermine them out of context, then I think that person should be ostracized and socially rejected," Franks said.

"There should be a political price and a social price to pay. People should have the right to speak off-hand and joke among their friends without worrying that they are going to bring down the Western world."