Plumbers...Local No 75 v. Morris Plumbing (E.D. Wisconsin). "...counsel is on notice that any future instance of the presentation of nonexistent case authority will result in sanctions."

midwestfrontierai.substack.com

Although it did not change the outcome of the case, Plaintiffs cited a nonexistent case, found another case at hallucinated reporter no.). See test at the end for warnings about AI hallucinations.