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https://www.lemonde.fr/en/m-le-mag/article/2026/04/19/when-dashes-give-away-chatgpt-usage_6752585_117.html

Le Monde's Guillemette Faure examines how the presence of the em dash in a text can reveal that its author relied on artificial intelligence.

On March 27, French Prime Minister Sébastien Lecornu expressed satisfaction on X about the relatively healthy state of the country's public finances. "When you stick to a simple approach — seriousness, stability, control — the accounts improve without any harsh measures," he wrote. "We'll keep going — with caution — to bring the public deficit below 5% of GDP in 2026."

The tweet could have just gone unnoticed. Instead, it triggered a minor storm over its construction.

"Unbelievable," exclaimed tech entrepreneur and media personality Laurent Alexandre, also on X. "This tweet was written by ChatGPT." His evidence: the "big double dashes." Someone replied that perhaps the real issue was not the prime minister using AI to write his tweets, but that a digital specialist of his level was still referring to the "big double dash."

This is because the em dash, the longest dash of all, has acquired the label "ChatGPT dash" since it is used to identify writing produced with this AI.

It happened close to home

Unlike Proust or Flaubert, most of us have had little reason to use this kind of punctuation, generally reserved for dialogue. Even then, we would have had to know it existed and, more importantly, know how to type it on a keyboard. ChatGPT has taken it over and, just like its bullet points, bold words, emojis or arrows it uses everywhere, it sprinkles em dashes throughout its answers.

The em dash is now flourishing in press releases, self-congratulatory LinkedIn posts and university application letters. To the point that what once seemed like typographical refinement has become a telltale sign. A bit like spotting a frozen food delivery van parked outside your favorite restaurant – it could be a coincidence, or maybe not.

A new "handwritten" text police now targets anyone – from Le Figaro journalist Eugénie Bastié wondering about modernity to Barack Obama congratulating tennis player Coco Gauff