The study found that postings on weibo by 100 opinion leaders fell by 10% in the two months following a warning from a senior official last August that popular microbloggers should be more responsible online.
The lawsuit filed by Mr. Hinojosa is still pending, and it claims that postings on the Internet by the tournament organizers that suggested Mr. Cavazos cheated were defamatory and inflicted emotional distress upon him and his wife.
She complained of suffering enormous distress from what Cyrus had done and said that her actions had the potential to damage her career, since the American had deliberately given the impression that postings of O'Connor's tweets reflected her current condition.
But Judges Alex Kozinski and Sandra S. Ikuta ruled that postings from users in a part of their profile designated "additional comments" could not subject the site to liability because it was essentially uninvolved in creating them.
Paul Gimigliano, a C.I.A. spokesman, said that the blogs were intended to "encourage collaboration" on business issues but that postings "should relate directly to the official business of the author and readers of the Web site".
Ezra Levant, a Canadian conservative commentator who was to appear Tuesday with Ms. Coulter, said that postings on Facebook by people involved in the protest included suggestions that people bring vegetables, eggs "and I think there was something about sticks" to throw during her speech.
