O'Reilly, whose producers proudly ambush anyone who disagrees with him, has taken up as one of his pet causes the privacy of celebrities stalked by paparazzi.

"I think my favorite part about 'The Factor' is that they have no trouble reconciling their defense of celebrities' right to privacy with their intimidation of everyone else," Stewart said, showing unedited footage of O'Reilly segueing from an ambush of...