John Fletcher Lacey (May 30, 1841 - September 29, 1913) was an eight-term Republican United States congressman from Iowa's 6th congressional district. He was also the author of the Lacey Act of 1900, which made it a crime to ship illegal game across state lines, and the Lacey Act of 1907, which further regulated the handling of tribal funds. As the first federal conservation law, the Lacey Act of 1900 remains one of the foundations of conservation law enforcement.