William J. Biggy (January 23, 1859 - November 30, 1908) (died in the San Francisco Bay, near Alcatraz) was San Francisco Chief of Police 1907–08. He was appointed Chief of Police by Mayor Edward Robeson Taylor. Upon elevation to the position of Chief, Biggy declared, as do most new chiefs in San Francisco, that he would "clean up" the department. Declaring a "shake-up" the department has not experienced in many years on his first day in office. One of his first acts was to demote his predecessor, Chief Jeremiah F. Dinan to the rank of patrolman. (New York Times, September 21, 1907 pg. 1)