BERLIN, 24 May 2006 — A Moroccan man won a landmark legal victory yesterday when Germany’s highest court set strict limits on the ability of police to trawl electronic databases at random in search of possible terrorists.

The ruling, which will force seven of Germany’s 16 states to review their police laws, came amid fierce debate in the United States and other countries over the balance between security and citizens’ rights in the battle against terrorism.

The Constitutional Court said general data trawling, for example to identify foreign male Muslim students, was only lawful if there was a concrete threat to Germany or one of its regions, or a danger to human life or freedom.

“A general threat situation, of the kind that has existed continuously in regard to terrorist attacks since Sept. 11, 2001, or external political tensions, is not sufficient,” the court said.

“The pre-condition is, rather, the existence of further facts pointing to a concrete danger, such as the preparation or commission of terrorist attacks.”

Police union chief Wolfgang Speck said: “The police would like someone to explain to them, and above all to the public, how they are supposed to combat international terrorism sensibly and effectively with falling staff numbers and a non-existent legal basis.”

The case arose from a complaint brought by a 27-year-old Moroccan student, whose name has not been disclosed, after the Sept. 11 attacks on the United States.

German police had begun scanning local authority and university databases to identify foreign Muslim men aged 18 to 40 who were current or former students.

Men who met that description were then subjected to further police checks in an attempt to uncover more Al-Qaeda “sleepers” like the three Hamburg-based Arab students who led the suicide hijack attacks on America. None were actually found.

The German court ruling said police data trawling of certain types of people, if it became publicly known, could “reinforce prejudices and stigmatize the affected social groups in the perception of the public.”