For 71 years, Germany’s Der Spiegel magazine has prided itself on delivering high-quality journalism based on a simple premise: “Say it like it is.”

But now the prestigious Hamburg weekly has admitted publishing 55 articles by one of its journalists whose maxim was: say it like it isn’t.

Like the story of a Syrian teenager whose Damascus graffiti helped spark the brutal civil war – winner this month of Germany’s reportage of the year award. Or the Guantanamo prisoner who didn’t want to leave the US camp in Cuba. Or the small town in Minnesota with the “Mexicans Keep Out” sign.

Then there was the a recent five-page, 8,000-word article about Gayle Gladdis, a Bible-carrying American woman who takes the Greyhound bus to witnesses executions of strangers. “It was all perfect. Except it wasn’t true. None of it [was],” the magazine said.

Confronted by evidence of his deception, Relotius made a confession by degrees. But even that was problematic: he insisted he had interviewed the parents of the NFL player Colin Kaepernick, who staged protests by kneeling during the US national anthem, until their lawyer told the magazine: “This story has no basis.”

The news magazine admitted it is not sure how many of his 55 stories for it were inaccurate – nor is the journalist who has resigned after an internal investigation.

For Der Spiegel, even more troubling than the unknown scale of his deception, is how one of its staff managed to consistently outsmart its own fact-checking department -- supposedly the most rigorous in German journalism.

Suspicious colleague

His method for gaming the system was a nose for the offbeat and an eye for the precise – often banal – details on which Der Spiegel prides itself as proof its journalists are closer to the story.

In the case of Gayle Gaddis and her journeys to witness state executions, the journalist claimed to have accompanied her from her home in Missouri to Texas, starting at dawn. The price of her ticket: $141.

“She takes a seat front right and says she often gets nauseous on long trips,” he wrote, describing how the woman wore a crucifix chain and carried a yellowed bible. “Gladdis breathes deeply, presses her fists so tightly against their fists in her lap that the knuckles stand out white.”

Relotius’s career as a journalist – and fabulist – delivered another high-flying piece in which he infiltrated a militia guarding Arizona’s border with Mexico against illegal immigrants. The Spiegel journalist spent days with the militia in the desert, he said, and described everything right down to the tattoos on its members’ hands.

A suspicious colleague who worked on the same piece, and flagged concerns about the Relotius contribution, was not believed. Convinced he was right, he tracked down supposed interviewees in Arizona who had never met – nor spoken with – Relotius.

Confronted by his increasingly suspicious superiors, the 33-year-old said he worked honestly until a story evaporated or if he struggled to reach a key figure. Then he put pressure on himself to help things along, and began to fabricate.

“He helped himself to images, Facebook posts, YouTube videos, he looted old newspapers, obscure blogs,” the magazine added, “and, from these pieces, slivers, scraps and crumbs he created new creatures like a playful little God.”

Until he was exposed as a modern equivalent of Baron Münchausen, Relotius said he had not been aware of the potential damage his work had caused to the credibility of journalism in general – and Der Spiegel in particular.

“I am sick,” he said, “and I now have to allow myself be helped.”