In 1991, the U.S. Supreme Court ruled that the 1st Amendment does not protect the media from breach-of-contract claims by sources with whom it makes confidentiality agreements.
Jane Kirtley, a professor of media law and ethics at the University of Minnesota, said journalists should make strong efforts to put source material in the public domain.
"In this increasingly divided, partisan world, there are fewer people, sadly, who will take the reporter's word for it," Kirtley said.
Times Editor Russ Stanton said the paper had no intention of breaking its promise to its source. And he rejected contentions that the newspaper had shown favoritism toward Obama.
"Any regular reader of the Los Angeles Times could tell you that we have written plenty of stories about Sen. Obama that were less than flattering," said Stanton, who mentioned front-page stories that said the Illinois senator's budget proposals did not add up, that described how Obama fit right in with the bare-knuckled Chicago political culture and that said fellow community organizers believed he had gotten too much credit for the work he did for the poor in Chicago.
McCain's contention that Ayers attended the 2003 party apparently stemmed from another news article, in which the New York Sun reported on the same dinner, given for Khalidi as he was departing Chicago to take a position at Columbia University.
The Sun story describes a "commemorative book filled with testimonials" to Khalidi, including one from Ayers and his wife, Bernardine Dohrn. The story does not make clear whether the couple attended the dinner.
Democrats countered McCain's complaints by noting that the Republican has his own ties to Khalidi. The Arizona senator once headed a nonprofit group that gave grants to an institute Khalidi headed, money that was used to conduct polling in the West Bank.
Asked to comment on McCain's involvement with the Khalidi institute, campaign spokesman Michael Goldfarb replied, "You all can get a response as soon as you hand over the videotape."