Most states in the US, and indeed many jurisdictions around the world, have enacted some form of anti-spam legislation. But it's done nothing to stop the onslaught and indeed, the problem seems to be getting worse.

David Sorkin, Associate Professor of Law at the John Marshall Law School in Illinois, says the spam legislation is not only ineffective. It might actually backfire and make things worse.

His paper Spam legislation in the United States says the prohibitions vary across the states, from opt-out clauses to outright bans. But in the end, it makes no difference. The spammers are either ignorant of the laws, or they just don't care because they know they won't get caught.

Part of the problem, he says, is the geographic reach. And the variation from jurisdiction to jurisdiction makes it harder to police. "The vast majority of spam is sent across state lines. Even if the sender and recipient happen to be located within the same state, it is likely that the message will be routed through a server located elsewhere. Moreover, senders and recipients of spam usually are unaware of (and generally unable to determine) the other party's location. Some state laws contain specific provisions regarding their geographic reach, although several are silent on this question, producing uncertainty as to whether a state's law applies to a particular message."

He also makes the point that the states are so preoccupied with the fraudulent aspects of spam that they in effect legitimize non-fraudulent spam and make it easier for marketers to use it for prospecting purposes.

He says the can-spam Act of 2003 enacted by Congress is unlikely to be of much use either because of the international dimensions of the spam problem and other factors. And the focus on fraud could lead to a massive increase in the amount of spam sent by legitimate businesses.