The East German police file on Ingo Steuer, 39, was made public yesterday, causing a split in the sport’s establishment. The National Olympic Committee argues that Herr Steuer cannot represent Germany, while the German Skaters Federation says that his relationship with the Stasi should not be an issue.

Documents show that Herr Steuer, who represented united Germany in two Olympic Games, and became the 1997 pairs world champion, was an active and enthusiastic informer between 1985 and 1989. He reported back on confidential conversations with athletes, and tipped the Stasi that an ice skater was considering defection to France.

He was also used to observe Katrina Witt, East Germany’s star skater. Frau Witt herself had contact with the secret police, and garnered a number of privileges from the Stasi, including a new car.

"I did nothing that would have done any serious harm to anybody," said Herr Steuer, whose file was registered under the code name "Torsten". The file, however, makes clear that he formally pledged his services to the Stasi at the age of 18 and for four years supplied them with nuggets of information about the politics and love lives of his colleagues.

The Stasi infiltrated the whole East German sporting world. Since East Germany had been a major sporting power, Germany was eager after 1990 to tap into its athletic potential and leap to the head of the international medals tables. In the process, Stasi files were often overlooked.

Last week the National Olympic Committee said that it would remove Herr Steuer from the official delegation, and named Monika Schweibe, another leading trainer, as his replacement. But yesterday it emerged that Frau Schweibe, 56, was also a Stasi informer.

The dispute pits a genuine desire to tackle the past against an equally fervent wish to win medals. Trainers from the former East Germany are often very effective. Germany’s medal hopes for Turin hinge on the skating pair of Aliona Savchenko and Robin Szolkowy. Ms Savchenko is from Ukraine but her German citizenship was rushed through so that she could skate for Germany in Turin. Herr Steuer was the personal coach of the couple and was expected to steer Germany to at least a silver medal. "I’m not going to skate without him," Ms Savchenko said yesterday.

Herr Steuer challenged the National Olympics Committee (NOC) in a court in Berlin on Tuesday, and won the right to go to Turin. The NOC has duly registered him as part of the German team but will lodge an appeal today to stop him coming in any official capacity to the Games.

It is a tangled story that reflects Germany’s tangled history and post-war Communist rule. About 180,000 people have been officially identified as part-time Stasi informers; since many records were destroyed the actual figure may have been much higher. The Stasi used informants from across society — writers, lawyers, journalists, academics, actors, doctors, waiters and churchmen.

"It would not have been unreasonable to assume that at least one Stasi informer was present in any party of ten or twelve dinner guests," said John Koehler, who has written a history of the Stasi. Sport was particularly vulnerable. Two other officials with Stasi pasts, the ski jump trainer Henry Glass and the sports analyst Hans Hartleb, have also been banned from the Turin team.

IN THE FILES

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