For many, part of the appeal of social media sites is that they let users hide behind a cloak of anonymity—be it a thinly disguised handle known only to friends or an alias that lets a person post comments and blogs with virtual anonymity. Some users assume a public persona to comedic effect, such as when Dan Lyons blogged as the (fake) Apple (AAPL) CEO Steve Jobs.

But anonymity can take a more sinister turn—say, when a person uses it to create a real perception that they're someone else and then potentially maligns another person's character. A legal battle between Major League Baseball manager Tony La Russa of the St. Louis Cardinals and microblogging site Twitter is testing the limits of a person's ability to impersonate online. It could peel back the cloak of anonymity that propels much user-generated content.

On June 5 a complaint filed against Twitter with the Superior Court of California was moved to federal court by the San Francisco-based company. In it, La Russa accuses Twitter of trademark infringement and other infractions because the site allegedly failed to take down the account of someone who was pretending to be him. The impersonator had signed up for Twitter using the baseball manager's name and photo in April, and then posted comments that La Russa says impugned his reputation.

first to take twitter to court

Although several people have complained about impersonators on the microblogging site before, La Russa is the first to take the matter to court. Someone claiming to be the Dalai Lama earlier this year was suspended from the site, then later reappeared with the name "the UNOFFICIAL Twitter page of His Holiness the Dalai Lama." In May rapper and producer Kanye West complained on his personal blog about an imposter posing as him, and called Twitter "irresponsible and deceitful" for not doing anything to stop it; the site later removed postings by West's impersonator.

Twitter lets users post under any name they wish, real or imagined, so long as they make it clear if they're impersonating someone. The site's terms of service clearly prohibit impersonation and postings "intended to mislead, confuse, or deceive others." The company has frequently enforced these terms by barring certain accounts and users.

Yet as growing numbers of people join Twitter, policing the population becomes more difficult. This has legal experts wondering whether and when Internet companies might be forced to take more aggressive steps to stop impersonation. "At some point will we redraw the balance and give protection to individuals?" asks Harry Rubin, a partner at New York law firm Ropes & Gray.

If La Russa's case goes to trial, it may address these questions. Officially, the suit is active. But La Russa's attorney, Gregory McCoy of Gagen, McCoy, McMahon, Markowitz & Raines, tells BusinessWeek that he recently reached a settlement by phone with lawyers from Fenwick & West, the firm representing Twitter. On June 6, however, Twitter co-founder Biz Stone denied that a settlement had been reached. "Twitter has not settled, nor do we plan to settle or pay," Stone wrote in a blog entry. "With due respect to the man and his notable work, Mr. La Russa's lawsuit was an unnecessary waste of judicial resources bordering on frivolous."

La Russa Cites Trademark Infringement

"I'm not in agreement with the spokesperson's statement," McCoy responds, referring to Twitter co-founder Stone. "My understanding was that we had settled it." Although Twitter removed the case to federal court, according to the records of the Superior Court of California, McCoy believes this was done as a provision, "in case we didn't work something out." Twitter did not respond to a request for comment, and Fenwick & West declined to comment.

Currently, Web companies are protected from being sued for content created and uploaded by their users under Section 230 of the Communications Decency Act of 1996, which states that Internet service providers can't themselves be treated as the publisher or speaker of content users post that is pornographic, defamatory, or otherwise illegal. Section 230 has been invoked to successfully uphold the immunity of Google (GOOG), MySpace (NWS), AOL, and Craigslist in suits that tried to hold those sites responsible for content posted by their users.

But La Russa's complaint hinges on a separate matter: trademark infringement. Because the impersonator's Twitter account displayed the text "Tony La Russa is now using Twitter" and provided his name, photo, and a Web address containing his name, La Russa is arguing that Twitter is complicit in a kind of false endorsement of its service. "It's sort of an argument of 'You're defrauding the marketplace because you're basically saying this person is endorsing the service,'" says New York attorney Rubin.

Other sites are also grappling with how to protect users from potentially harmful impersonation. On June 9, Facebook said it would let users sign up for custom user names on the site. In a company blog post, it asked people with trademarked "or other protected names" to e-mail the company ahead of the Jun. 13 opening of the feature with requests to reserve those names.

Facebook applies stricter rules

Whatever the outcome of the case, Twitter appears to be taking a lesson from it. On June 6 the company announced that it plans to begin experimenting with a "verified accounts" service to authenticate the identity of select users on the site. Included in the initial program will be "public officials, public agencies, famous artists, athletes, and other well known individuals at risk of impersonation," Twitter's Stone wrote in a blog post, adding that verifying businesses is also a possibility. The company hasn't detailed how it intends to verify these individuals.

Twitter is following in the footsteps of Facebook. "When any user contacts Facebook to report a fake account—including a celebrity—we investigate the situation and will remove that page or profile if appropriate," says Brandee Barker, spokeswoman for Palo Alto (Calif.)-based Facebook. When the company is tipped off to a potential impersonator, it asks users to send in copies of their identification. Facebook goes a step further in asking that all of its users, even noncelebrities, use their real names to help avoid the problems that potentially arise from anonymous users.

Will Twitter soon start asking all users to show ID? Its doubtful, says the Electronic Frontier Foundation's Matt Zimmerman, who points out that the anonymity afforded by sites such as Twitter ensures that the Web is a powerful outlet for free speech. When sites enforce authentic identity, "it makes them very attractive choke points for people who want to silence free speech," Zimmerman says.

Click here to see a copy of Tony La Russa's complaint against Twitter.

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