The German Constitutional Court (the Bundesverfassungsgericht) ruled today on a what the German press is calling "a new basic right" - one that guarantees the confidentiality and integrity of computer systems.

The court spelled out the protection as part of its judgement (available in German) on the constitutionality of a law that let police infiltrate a suspect's computer by using trojan horses or rootkits. Such police powers had been repeatedly called for by the Federal Minister of the Interior, Wolfgang Schäuble, as well as the head of the German Federal Police.

The first implementation of the law by the Federal state of Nordrhein-Westfalen was struck down by the court, who said that such invasions of computer systems clashed with the "general personality right" - a right the court had previously derived from the Constitution's basic right to human dignity and personal freedom.

It's easy to see this as a new right in itself - but perhaps it is better to understand it, as the court did, in terms of a reasonable (and perhaps overdue) updating of the language of traditional human liberties.

Just as EFF has argued that the United States' Constitution's wording against warrantless searches should protect the privacy of the contents of your computer and email as strongly as it does the privacy of real world "papers and effects", so the German constitutional court said that the 1949 constitution protects the digital contents of a PC or laptop (or any other "informationstechnischer Systeme") against secret surveillance as tightly as your possessions in the real world. A virtual trojan horse is as uncivilized a tool of the police as sneaking an officer into your own home.

As with an earlier decision on wiretapping, the court also held that the essential core of private life must never be surveilled by the state: the act of practicing a religion, say, or conversation between family members.

Germany, a country with a proud (and hard-learned) modern tradition of protecting the privacy of its citizens, now has some interesting new legal territory to explore. On the modern Internet, the core of citizen's private life is increasingly distributed among many different computers. A conversation between family members can take place on Facebook (or StudiVZ, its German equivalent); the private contents of your home PC may be backed up on an online storage service.

German law enforcement will have to tread carefully not to violate its citizens' basic rights in a world where even the most private life is remotely accessible and spread far and near. We hope that the techniques they develop will be shared and spread with the rest of the world's law makers and law enforcement community.