There's only one question remaining as the first presidential debate is just over one month away: Who's going to be the moderator?
The answer to that question won't be announced until after Labor Day, a source familiar with the subject told CNNMoney's Dylan Byers Wednesday. The Commission on Presidential Debates had originally planned to unveil the moderators later this month, but it has since pushed back the announcement until after Sept. 5, according to the source.
As usual, the bipartisan Commission is working to find moderators who are not likely to face backlash for showing bias during the debates, but according to Byers' source, finding a journalist immune to accusations of partiality has been a pretty difficult task given how frequently Donald Trump has challenged members of the media for their reporting.
The Commission is hoping to find a moderator who will remain in the background, not becoming embroiled in the story. However, the Republican presidential nominee's strident attacks on the media and his complaints about impartial treatment all but guarantees whoever the moderator is will come under fire from conservative circles.
All this together has made choosing the moderators an even more tedious task than usual for the Commission, which has run every presidential debate since 1988. Add to that the fact that, given her 30-year career in public life, Hillary Clinton has developed quite a few close relationships with media personalities over the years.
For that very reason, the source said, PBS' Charlie Rose is unlikely to moderate the Trump-Clinton debates, because in 2012, the seasoned interviewer and Clinton were in a "close group" of celebrities and politicians who spent a Christmas vacation at Oscar De La Renta's home in the Dominican Republic, according to a Wall Street Journal report.
Also in 2012, ABC News became the subject of some scrutiny from conservative media — most notably The Daily Caller — for a revelation that President Barack Obama was a guest at the 1991 wedding of correspondent Martha Raddatz, who moderated the vice presidential debate. ABC dismissed the dustup as "absurd."
In yet another situation, former CNN journalist Candy Crowley, who was moderating a debate between Obama and 2012 Republican presidential nominee Mitt Romney, interjected herself into the debate to offer the president an apparent assist in his response to accusations from Romney that he did not initially refer to the Benghazi attack as a "terror attack." She later admitted Romney was "right."
"She obviously thought it was her job to play a more active role in the debate than was agreed upon by the two candidates, and I thought her jumping into the interaction I was having with the president was also a mistake on her part, and one I would have preferred to carry out between the two of us, because I was prepared to go after him for misrepresenting to the American people that the nature of the attack," Romney said of the altercation during a 2014 interview with Hugh Hewitt.
In the Commission's quest for a moderator this go 'round, the CNN report noted, it is unlikely Fox News' Megyn Kelly, one of 2016's most prominent reporters, will be picked for the job. Kelly's prominence, some would argue, is largely due to her confrontation with Trump during the Republican primaries, making her an unviable option in the Commission's view.
The Commission is instead searching for moderators who, on top of being capable reporters who are able to successfully moderate a presidential debate, have no ties to Trump or Clinton and no past altercations with either candidate.
In the past, the Commission has leaned on media veterans like Bob Schieffer and Jim Lehrer, both of whom moderated 2012 presidential debates, but retired after the election. Schieffer briefly joined the Commission's board of directors, but left earlier this year after returning as a contributor for CBS News.
While both men have been criticized for their reporting in the past, they are largely trusted by the general public. In a statement to CNN, Schieffer compared the debates to baseball, saying, "Nobody comes to the baseball game to see the umpires. They come to see the players."
Schieffer voiced trust in the Commission's ultimate decision, telling Byers there are "some really good" options available.
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