Warning: Prince Xenu could destroy the Net

The sun was still rising when Dennis Erlich heard the knock on the door he had been dreading ever since he left the Church of Scientology in 1982. It was 7.30am on 13 February this year, and Erlich, a former minister of the church, had just stepped out of the shower.

Armed with a civil writ of seizure, and accompanied by a Glendale County police officer, 20 Scientologists entered his Californian home. They searched his rubbish bins and every one of his computer files until they found what they were looking for: the secrets of the universe.

Seven hours later they departed, but not before they had deleted and confiscated various computer files and discs. The secrets of the universe they had recovered were those postulated by L Ron Hubbard, a former science- fiction writer and the founder of the Church of Scientology. Mr Erlich had been posting Scientology material on the Internet in an attempt, he says, "to alert people to the dangers".

The secrets are part of the sacred writings of Scientology, but are also treated as trade secrets subject to copyright laws. Even the term Scientology is a federally registered trademark. Scientologists can pay anything up to $250,000 for a series of special courses to learn the secrets - that, for example, 75 million years ago, earth was part of a galactic confederation ruled by the evil Prince Xenu. When Dennis Erlich posted some of the writings on the Internet for millions to read, the cult decided to sue him for violating copyright laws. One Scientologist explained why: "It's not helpful to see [the secrets] before you have gone up a carefully gradient path of knowledge."

If it had ended there, the case would have been forgotten as just another minor incident involving a global cult and the new medium for global communication. Writs for libel and copyright infringement on the anarchic system are being issued in ever-increasing numbers.

But the case, which comes to court this month, has potentially catastrophic implications for the Internet. The Scientologists have also named a company called Netcom in their lawsuit. Netcom is Erlich's Internet provider. If the American courts decide in favour of the Scientologists, such companies (the equivalent of Demon, Easynet and the like in the UK) will be responsible for messages put on to the Net by their subscribers. That is analogous to British Telecom having to eavesdrop on every telephone conversation in Britain.

Mr Erlich is not the Scientologists' only target. In July, the church issued a lawsuit against a Mr Lerna, an Internet user, Digital Gateway Corporation, an access provider, and the Washington Post, which reported on the case. And 10 days ago US marshals raided the homes of former Scientologists Larry Wollersheim and Robert Penny, who run an electronic bulletin board. "There are a lot of bucks riding on this," says Dan Liepold, a lawyer who has been involved in many Scientology cases. "They'll shut down the damn Internet if they win."

Of course, the Scientologists want no such thing. They merely want to put an end to what they consider to be copyright violation and the "anarchy created by some Net users". In their eyes, companies that provide access to the Internet, and even bulletin boards which provide space on the Net, should be held responsible for what is carried on the system.

Like BT, Netcom does not monitor what is carried on its system. It will argue in court that it is in effect a landlord in cyberspace: it provides the space but cannot, as legal precedent has established, be responsible for what happens in it. The fact that Netcom has to resort to such abstruse arguments reflects the bizarre nature of this case. The Internet is uncharted legal territory, and the courts will have to go where no law has gone before.

If Netcom did not exist, it says, everything it carries would simply switch to another service provider. "Going after us is like trying to stop water flowing through a colander by blocking up just one of the tiny little holes," says Randy Rice, one of Netcom's lawyers.

Mike Goodwin, a lawyer at the Electronic Frontier Foundation, an American pressure group that has taken up the cases of both Netcom and Dennis Erlich, believes people "have to adapt their understanding to the way the law should work to a new medium which is structured differently. This is the first medium in the history of mankind in which individuals have been able to reach mass audiences without any intervening editorial control". The individual becomes the writer, publisher and broadcaster, and for the price of a local call can reach as many people as Rupert Murdoch.

Dan O'Brien, a journalist at Wired magazine, says: "Everyone on the Net is in some way a carrier. The Scientologists are used to going after the traditional media when they don't like something, but in this case they are struggling to find anything they can get hold of."

Netcom describes the Scientologists as the "perfect plaintiff". If anyone had to bring this case, it might as well be a cult that is widely regarded with suspicion. "But," says Randy Rice, "my clients would be much happier if there were laws dealing with this, because this is very expensive. We are spending hundreds of thousands of dollars just trying to figure out what the law is."

In the past year the US has seen a rash of proposals and congressional bills to deal with what some people view as a dangerously out of control phenomenon. The Senate has been considering the Communications Decency Act of 1995 - which would hold all on-line services in America criminally liable for any postings on their system. There is also the recently passed Digital Telephony Bill, which states that any public communications network that carries both voice and data must be designed so federal authorities can listen in.

Meanwhile, Senator James Exon wants to make the Internet "safe for children". He has suggested increasing the penalties for people who break the law on the Internet but, like the Scientologists, he has tried to hold not only the individual author responsible, but also the companies that distribute the material.

Shari Steele, another lawyer at the Electronic Frontier Foundation, believes that "we are going to be see some bad litigation in the years to come before it gets resolved. It is inevitable that laws will be passed. I just hope they are combined with clear thinking about the ramifications". The irony, of course, is that a cult set up by a science fiction writer - who taught his followers to believe in space-age galactic civilisations - should be the one to threaten what was once science fiction, but is now science fact.