Annonymity On The Net

Is there a First Amendment right to speak annonymously on the internet? A recent California Appellate (Krinsky v. Doe 6) case holds that, under certain circumstances, there is. In that case, plaintiffs argued that the identity of a individual who posted "scathing verbal attacks" on an online message board against corporate officers of a Florida company should be exposed. Plaintiffs served a subpoena to have the identity of "Doe 6" disclosed but the request was denied.