It's right there in the article. A clerk wondered why there was so much white space. They don't use LLMs at that court.
> these attacks do not seem to be succeeding, even when a judge isn’t reviewing documents with his own eyes. Brazil’s AI system caught the hidden text before it was processed, Spader noted. And in Elliott’s case, prompts were “exposed, in each of those settings, the moment a human being actually looked at what the machine produced,” Spader said.
There's a long post near the top of this comment section calling the article "garbage" because of this mistake.