Hillary Clinton and her aides are pressing moderator Lester Holt to "fact-check" Donald Trump during the debate tonight.  Debate moderators cannot "close their ears to Donald Trump's lies; it will extend an unfair bias to Donald Trump," Clinton's press secretary said.  The Clinton camp claims that it will be like giving Trump more time if Hillary has to do her own fact-checking.

But the Commission on Presidential Debates doesn't want the moderators put in that position.

CNNMoney:

But Janet Brown, executive director of the commission, which organizes the debates every four years, said on CNN's "Reliable Sources" that "I don't think it's a good idea to get the moderator into essentially serving as the Encyclopedia Britannica."

Once the fact-checking door is open, "I'm not sure, what is the big fact, and what is a little fact?" She added, "Does your source about the unemployment rate agree with my source?"

Trump campaign aides have staked out a similar position. Some of them say a pro-fact-checking stance is really an anti-Trump stance.

Trump campaign manager Kellyanne Conway responded to the Clinton camp's call for aggressive moderating by saying on ABC, "I really don't appreciate the campaigns thinking it is the job of the media to go and be these virtual fact-checkers."

This point of view stipulates that the candidates will challenge each other without the moderator stepping in. As Lehrer put it on CNN: "The moderator's job is to keep the flow going."

The counterargument goes like this: An actor or a robot could keep track of time. A journalist needs to represent the viewers and help make the truth known.

"We hate to leave absolute errors of fact on the table," former debate panelist Ann Compton said.

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So is fact-checking a part of the job or not? On Monday, it will be up to Holt to decide.

The commission "asks independent, smart journalists to be the moderators and we let them decide how they're going to do this," Brown said.

Holt is well aware of the controversy. While he has not commented, one NBC staffer close to Holt said, "Lester is not going to be a potted plant." Another staffer seconded that sentiment.

The fact-checking debate revolves around this fact: Trump is unusually fact-challenged.

While both candidates have been criticized for shading the truth this year, top fact-checkers say Trump's lies are in a league of their own.

After reviewing every statement made by both Clinton and Trump for a week, Politico concluded that "Trump's mishandling of facts and propensity for exaggeration so greatly exceed Clinton's as to make the comparison almost ludicrous."

Trump even said last week that Holt is a Democrat, when in fact Holt is a registered Republican.

If Holt intervenes in this debate, it will create a groundswell of support for Trump.  It will appear as if the liberal media is ganging up on the candidate – 2 against 1, with Hillary and the press sticking it to Trump.

Is Clinton so ill prepared that she can't do her own fact-checking?  Her claim that she would take most of her time allotted to correct Trump's lies and misstatements misses the point.  Highlighting Trump's ignorance and dishonesty might be a better tactic than showing the voters just how smart she is on the issues.

"Fact-checking" is a losing issue for Clinton.  If Holt weighs in, it will only help Trump.