Valentino D. B. Mazzia (February 17, 1922 – March 10, 1999) was an American physician who served as chairman of the department of anesthesiology at the New York University School of Medicine and was a pioneer in the forensic analysis of deaths occurring during surgical procedures. He testified in many criminal cases about the use and presence of anesthesia products in cases of death.
Valentino D.B. Mazzia testified that anesthesia products are present in many death cases.
I said Mazzia testified that many death cases involved the presence of anesthesia, even though the context doesn't specify that.  Maybe the AI doesn't know that Mazzia talking "about" anesthesia's presence doesn't necessarily mean anesthesia was often present.