Three years ago, Mr. O’Keefe said, he read “Rules for Radicals” by the left-wing icon Saul Alinsky, the Bible for many community organizers, including those at Acorn, the Association of Community Organizations for Reform Now. He absorbed in particular Rule 4: “Make the enemy live up to its own book of rules.”…

Liz Farkas, a Rutgers student who called Mr. O’Keefe “a nice guy and a loyal friend,” said she grew disillusioned after he asked her to help edit the script of a Planned Parenthood sting.

“It was snippets to make the Planned Parenthood nurse look bad,” Ms. Farkas said. “I said: ‘It has no context. You’re just cherry-picking the nurse’s answers.’ He said, ‘Okay’ — and then he just ran it.”

Asked whether the left-leaning documentaries of Michael Moore do not do the same, Ms. Farkas said: “Michael Moore goes after the rich and powerful. James isn’t doing that. He goes after low-level bureaucrats and people who are trying to help low-income people.”