SAN FRANCISCO (KTVU) - Face-to-face in the first presidential debate Monday night, Donald Trump and Hillary Clinton's statements at times flew in the face of the facts.
With two controversial candidates this year, fact-checking has become a big issue that could impact the way undecided voters make their decision, said Eric Schickler, chair of the U.C. Berkeley political science department.
At least a half dozen organizations had non-partisan fact-checkers working to verify statements made by both candidates.
KTVU monitored the sites and pulled some examples from two non-partisan organizations: FactCheck.org and Politifact.com.
Clinton said her economic plan would create 10 million new jobs, but factcheck.org said at most, Clinton's plan would create 3.2 million.
Trump asserted that the U.S. trade deficit is $800 billion dollars, but FactCheck.org called that misleading, saying the deficit is not that high.
On Iran, Clinton hit back at Trump's criticism of her support for the nuclear deal, saying it stopped Iran's nuclear program without violence.
Politifact checkers said Clinton is correct.
On trade, Trump accused Clinton of flip-flopping on the TPP, short for the Transpacific Partnership trade deal.
On that, Politifact checkers said Trump was right.
As for Trump's flip-flop, questioning President Obama's birthplace he was pressed by moderator Lester Holt and responded by accusing Hillary Clinton of starting the birther question.
Not true, according to multiple fact-checkers.
"Often the feeling is going to trump so to speak the facts," said Professor Schickler, "One thing that research has shown is that it's very hard to persuade people to change their minds about facts."
Professor Schickler says often people are predisposed to believe their candidate, no matter what the facts say.
"Your partisanship and your prior support for a candidate really impact how you interpret what they say and also how you respond to fact-checking, so it's really a narrow slice of voters that this kind of thing can affect," Schickler said.
He estimates about 40% of voters have decided on Trump, about 40% for Clinton, no matter what the candidates say. The fact-checking he says will most likely impact those 20% of undecided voters and how they view the issues.
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