CHA's lawyers fined $59,500 after ChatGPT invents a court case

A Cook County jury ordered the Chicago Housing Authority to pay more than $24 million to two children poisoned by lead paint in one of its apartments. The authority's law firm, Goldberg Segalla, then filed a post-trial motion citing an Illinois Supreme Court case that does not exist. A lawyer there had used ChatGPT and not checked its output. She was fired, and the firm apologized. The signing partner repeatedly told the court only one citation was wrong, but the plaintiffs found more false citations and quotes in the firm's filings. On December 5, 2025, Judge Thomas Cushing sanctioned the partner $10,000 and the firm $49,500. He faulted their misrepresentations more than the AI use itself.