Diane Sawyer appeared on Wednesday's "O'Reilly Factor" to talk about ABC's political coverage--and to assure Bill O'Reilly that it would be scrupulously fair and balanced during the 2012 campaign.
O'Reilly touted a study that said that the media's coverage of the 2008 presidential campaign was tilted in favor of Barack Obama.
"You, DIane Sawyer, are going to be held accountable for how your news operation treats both candidates," he said.
"We are really proud of our team and what we're going to do," she said, reeling off the names of some of the ABC News team as evidence for the division's professionalism.
"But they're all liberal people in real life," O'Reilly said. "You know that."
"I do not know that," Sawyer said. She stressed that ABC had covered the Tea Party extensively, and was thinking of devoting more resources to airing "both sides" of major issues. O'Reilly seemed skeptical, saying he was "concerned as an American" that the networks were not being fair.
"Look at what we do," Sawyer replied. "Look at what we do."WATCH: