In a blink, the wisdom of the crowd became the fury of the crowd. In the last few days, contributors to Wikipedia, the popular online encyclopedia, have turned against one of their own who was found to have created an elaborate false identity.
Under the name Essjay, the contributor edited thousands of Wikipedia articles and was once one of the few people with the authority to deal with vandalism and to arbitrate disputes between authors.
To the Wikipedia world, Essjay was a tenured professor of religion at a private university with expertise in canon law, according to his user profile. But in fact, Essjay is a 24-year-old named Ryan Jordan, who attended a number of colleges in Kentucky and lives outside Louisville.
Mr. Jordan contended that he resorted to a fictional persona to protect himself from bad actors who might be angered by his administrative role at Wikipedia. (He did not respond to an e-mail message, nor to messages conveyed by the Wikipedia office.)
The Essjay episode underlines some of the perils of collaborative efforts like Wikipedia that rely on many contributors acting in good faith, often anonymously and through self-designated user names. But it also shows how the transparency of the Wikipedia process — all editing of entries is marked and saved — allows readers to react to suspected fraud.
Mr. Jordan's deception came to public attention last Monday when The New Yorker published a rare editors' note saying that when it wrote about Essjay as part of a lengthy profile of Wikipedia, "neither we nor Wikipedia knew Essjay's real name," and that it took Essjay's credentials and life experience at face value.
In addition to his professional credentials and work on articles concerning Roman Catholicism, Essjay was described in the magazine's article, perhaps oddly for a religious scholar, as twice removing a sentence from the entry on the singer Justin Timberlake, which "Essjay knew to be false."
After the article appeared, a reader contacted The New Yorker about Essjay's real identity, which Mr. Jordan had disclosed with little fanfare when he recently accepted a job at Wikia, a for-profit company.
In an e-mail message on Friday, The New Yorker's deputy editor, Pamela Maffei McCarthy, said: "We were comfortable with the material we got from Essjay because of Wikipedia's confirmation of his work and their endorsement of him. In retrospect, we should have let our readers know that we had been unable to corroborate Essjay's identity beyond what he told us."
The New Yorker editors' note ended with a defiant comment from Jimmy Wales, a founder of Wikipedia and the dominant force behind the site's growth. "I regard it as a pseudonym and I don't really have a problem with it," he said of Mr. Jordan's alter ego.
On Thursday, Mr. Wales, who is traveling in Asia with intermittent Internet connections, stuck by that view. In a statement relayed through Wikipedia's public relations officer, he said that at that time, "Essjay apologized to me and to the community at large for any harm he may have caused, but he was acting in order to protect himself.
"I accepted his apology," he continued, "because he is now, and has always been, an excellent editor with an exemplary track record."
But the broad group of Wikipedia users was not so supportive. Mounting anger was expressed in public forums like the user pages of Mr. Wales and Essjay. Initially, a few people wrote to express support for Essjay, along the lines of WJBscribe, who left a message saying: "Just wanted to express my 100 percent support for everything you do around here. I think you were totally entitled to protect your identity. Don't let all the fuss get you down!"
By Saturday, the prevailing view was summarized in subject lines like Essjay Must Resign, and notes calling Mr. Jordan's actions "plain and simple fraud."
Some Wikipedia users argued that Essjay had compounded the deception by flaunting a fictional Ph.D. and professorship to influence the editing on the site.
"People have gone through his edits and found places where he was basically cashing in on his fake credentials to bolster his arguments," said Michael Snow, a Wikipedia administrator who is also the founder of The Wikipedia Signpost, the community newspaper for which he is covering the story. "Those will get looked at again."
In a discussion over the editing of the article with regard to the term "imprimatur," as used in Catholicism, Essjay defended his use of the book "Catholicism for Dummies," saying, "This is a text I often require for my students, and I would hang my own Ph.D. on it's credibility."
Over time, Wikipedia users said, Essjay did less editing and writing and spent more time ensuring that the encyclopedia was as free of vandalism and drawn-out editing fights as possible.
By Saturday, Mr. Wales changed his mind about the episode. He cleared off the "talk" section of his own Wikipedia user page — usually cluttered with personal requests, policy debates and compliments — so that "this statement gets adequate attention" and announced that he had "asked Essjay to resign his positions of trust within the community." He said "that my past support of Essjay in this matter was fully based on a lack of knowledge about what has been going on."
Complicating matters for Mr. Wales was that Essjay had been hired as a community manager by Wikia, which Mr. Wales helped to found in 2004. Mr. Jordan no longer works for Wikia, the company said.
Mr. Snow said the Essjay case "is about the community, the trust the community depends on in terms of being able to review the work we each do."
"Even though you don't necessarily know these people personally," he added, "you see the work enough times and get to know that work."
Mr. Jordan announced his resignation from Wikipedia on his Essjay user page on Saturday night. In a brief note below, he said simply, "It's time to make a clean break."
That page had been a model of industry, with tallies of the more than 20,000 articles he edited and statements of personal philosophy and Wikipedia policy. Where there had been the motto in Latin, "Tu ne cede malis sed contra audentior ito" ("Yield not to misfortunes, but advance all the more boldly against them," according to some translations), there is a stark rectangular black box with the word "retired" written in white capital letters.
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