As a result, most of the e-mail industry has turned its attention toward technology, rather than litigation, as the primary means for combating spam, Osterman said.
Dave Baker, vice president of law and public policy at Earthlink, said that despite Earthlink's aggressive use of Can-Spam, technological solutions to the spam problem remain the company's main focus.
"You've got to stop [spam] from getting to the customers' machines. If you're suing a spammer, you're going after them for damage that's already been done," Baker said. "The biggest single element remains technology solutions. None of these companies are relying solely on litigation."
Each of the four major e-mail providers is involved in a nationwide effort to develop e-mail "authentication" technology that would make it harder for spammers to disguise their messages.
And while Can-Spam may be a failure so far from the standpoint of consumers, whose inboxes haven't gotten any cleaner in the year since the law passed, that doesn't mean it's having no effect, said Anne Mitchell, executive director of the Institute for Spam and Internet Public Policy.
"It's given prosecutors some very good tools, and if they wield them properly they can be successful," Mitchell said. "It was never about making spammers stop, it was about making what they were doing illegal so we could force them to stop. There's never 'instant anything' when you pass a new law. Look at any of the civil rights laws -- it's not like they passed and suddenly we had a utopian society."
The lone bright spot in the fight against spam appears to be America Online. In December, the nation's largest e-mail provider reported a drop-off both in the volume of e-mail hitting its network and in the amount of spam delivered to users' inboxes in 2004. AOL fielded 1.6 billion e-mail messages in 2004, down from 2.1 billion in 2003, which AOL attributes almost entirely to a decrease in the amount of spam hitting its network.
"We think the primary reason that spam is down on the service is because of our spam filtering, but we also absolutely believe that the federal Can-Spam law has had a deterrent effect," AOL spokesman Nicholas Graham said. He pointed out that AOL is based in Virginia, home to the nation's stiffest anti-spam law and first convicted spam felon.
Graham acknowledged that AOL has no way of measuring what portion of the drop-off can be attributed to legislative efforts. And if the laws have scared some spammers away from AOL, the effect hasn't carried over to the online population at large, Postini's Smith said. "It's quite possible that that's only true about the AOL domain. We're not seeing that trend on a whole across the Internet."
Yahoo, Earthlink and Microsoft have not released end-of-year spam statistics.
Tim Murtaugh, a spokesman for Virginia Attorney General Jerry W. Kilgore (R), said while the effects may not have trickled down to users yet, the state and federal laws will eventually take their toll on spammers.
"The people out there who are the spam kingpins, I'm certain that they're aware of what we're doing here. I'm sure it will have at least a psychological impact in that they know we're serious," Murtaugh said. "We predict that it will make people have second thoughts. I don't think they ever thought what they were doing was going to land them in jail."