From the people who brought you the Reichstag fire

Spy Fired Shot That Changed West Germany

It was called “the shot that changed the republic.”

This photograph of Benno Ohnesorg being cradled by a woman after he was shot during a demonstration in West Berlin in 1967 is among the most iconic images in Germany.

The killing in 1967 of an unarmed demonstrator by a police officer in West Berlin set off a left-wing protest movement and put conservative West Germany on course to evolve into the progressive country it has become today.

Now a discovery in the archives of the East German secret police, known as the Stasi, has upended Germany’s perception of its postwar history. The killer, Karl-Heinz Kurras, though working for the West Berlin police, was at the time also acting as a Stasi spy for East Germany.

It is as if the shooting deaths of four students at Kent State University by the Ohio National Guard had been committed by an undercover K.G.B. officer, though the reverberations in Germany seemed to have run deeper.

“It makes a hell of a difference whether John F. Kennedy was killed by just a loose cannon running around or a Secret Service agent working for the East,” said Stefan Aust, the former editor in chief of the weekly newsmagazine Der Spiegel. “I would never, never, ever have thought that this could be true.”