Robert George Siebecker (October 17, 1854-February 12, 1922) was an American jurist from Wisconsin.
Siebecker was born in the town of Sumpter, in Sauk County, Wisconsin. In 1878, he graduated from University of Wisconsin and in 1880, graduated from the University of Wisconsin Law School. While at the University, he meet Josephine La Follette, sister of Robert M. La Follette, Sr. and they would be married. Siebecker practiced law with La Follette. In 1890, Siebecker became a Wisconsin state judge serving until 1903. In 1903, he was appointed to the Wisconsin Supreme Court and in 1920 became Chief Justice of the Wisconsin Supreme Court and would die while still in office.[1][2]