He was born at Sommacampagna, Italy. He studied medicine in Padua, where he studied, with Fabrizio and Acquapendente. He became professor of pathology in 1568 and occupied the chair for 20 years.
Zacchi's most famous work is Quaestiones medico-legales, published in 1596, which covers a wide range of topics in forensic pathology, including homicide, suicide, infanticide, rape, and poisoning. It was the first book to systematically discuss the use of medical evidence in legal cases, and it became a standard reference for forensic pathologists for centuries.
In addition to his work in forensic pathology, Zacchi also wrote about other medical topics, including a book on the plague, a book on surgery, and a book on the effects of tobacco smoke.
He died in Verona, Italy.
Selected works:
* Quaestiones medico-legales (1596)
* De Peste (1579)
* De Chirurgia (1576)
* De Effectibus Fumi Nicotianae (1589)
* De Prognosticis ex Pulsibus (1610)
* De Hydrope (1611)
* Consilia medica (1612)