 After four days in jail, he was found with his wrist slit, apparently having committed suicide, although reports suggested for years afterwards that he had been murdered by Vigilants or by other individuals who were worried about repercussions should Sullivan confess what he knew about corrupt political figures.Sullivan was buried at Mission Dolores Cemetery near the southwest corner of 16th Street and Dolores Street in San Francisco on 31 May 1856.He left a wife and child in California, and another wife in New York.