He was a member of the California State Assembly from 1865-67, representing the 18th District. He was subsequently elected as a Republican to represent California's 3rd District in the 42nd Congress, serving from 1871-73.
He was the United States Attorney for the Northern District of California from 1876 to 1878, and was appointed Chief Justice of the Territorial Utah Supreme Court by President Ulysses S. Grant, but declined to serve. Coghlan said he refused the position, because he preferred San Francisco to Salt Lake City.
He practiced law in Oakland, California until his death at his home in Alameda at the age of 43.
SOURCES: Biographical Directory of the United States Congress, Los Angeles Herald, History of San Francisco (Clarke Publishing, 1931)